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  • 1.
    Abitbol, Tiffany
    et al.
    RISE - Research Institutes of Sweden, Bioeconomy, Biorefinery and Energy.
    Ahniyaz, Anwar
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation.
    Swerin, Agne
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation.
    UV-blocking hybrid nanocellulose films containing ceria and silica nanoparticles2018In: International Conference on Nanotechnology for Renewable Materials 2018, 2018, p. 503-515Conference paper (Refereed)
  • 2.
    Abitbol, Tiffany
    et al.
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation. The Hebrew University of Jerusalem, Israel.
    Kam, Doron
    The Hebrew University of Jerusalem, Israel.
    Levi-Kalisman, Yael
    The Hebrew University of Jerusalem, Israel.
    Gray, Derek G
    McGill University, Canada.
    Shoseyov, Oded
    The Hebrew University of Jerusalem, Israel.
    Surface Charge Influence on the Phase Separation and Viscosity of Cellulose Nanocrystals2018In: Langmuir, ISSN 0743-7463, E-ISSN 1520-5827, Vol. 34, no 13, p. 3925-3933Article in journal (Refereed)
    Abstract [en]

    counterions in the suspensions. The results suggest that there is a threshold surface charge density (∼0.3%S) above which effective volume considerations are dominant across the concentration range relevant to liquid crystalline phase formation. Above this threshold value, phase separation occurs at the same effective volume fraction of CNCs (∼10 vol %), with a corresponding increase in critical concentration due to the decrease in effective diameter that occurs with increasing surface charge. Below or near this threshold value, the formation of end-to-end aggregates may favor gelation and interfere with ordered phase formation.

  • 3.
    Abitbol, Tobias
    et al.
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation.
    Ahniyaz, Anwar
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation.
    Swerin, Agne
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation.
    UV-blocking hybrid nanocellulose films containing ceria and silica nanoparticles2018In: International Conference on Nanotechnology for Renewable Materials 2018, 2018, p. 503-515Conference paper (Refereed)
  • 4.
    Agyei-Amponsah, Joyce
    et al.
    University of Pretoria, South Africa.
    Macakova, Lubica
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation.
    DeKock, Henrietta
    University of Pretoria, South Africa.
    Emmambux, Mohammad
    University of Pretoria, South Africa.
    Sensory, Tribological, and Rheological Profiling of “Clean Label” Starch–Lipid Complexes as Fat Replacers2019In: Starke (Weinheim), ISSN 0038-9056, E-ISSN 1521-379X, article id 1800340Article in journal (Refereed)
    Abstract [en]

    Dietary fat is highlighted as one of the critical risk factors that contribute to a number of chronic diseases. In this study, the sensory profile, tribological, and rheological properties of starch–lipid complexes, as a potential fat replacer, is investigated. Starch–lipid complexes are formulated by incorporating food friendly chemicals (stearic acid and monoglyceride) into maize starch by wet-heat processing and compared with a commercial fat replacer. The starch–lipid complexes have good lubricating properties and are described by the panelists as being glossy, smooth, creamy, and easy-to-swallow. All the complexes exhibited a shear thinning behavior and had lower firmness, due to their non-gelling ability compared to the commercial fat replacer. The properties of starch–lipid complexes for non-gelling, good lubricating, smooth, and creamy can be related to the formation of amylose–lipid complexes and other properties. The complexes have the potential to produce non-gelling emulsions having a creamy and smooth texture with no adverse effect on the overall aroma and flavor.

  • 5.
    Andersson, I. M.
    et al.
    Lund University, Sweden.
    Glantz, M.
    Lund University, Sweden.
    Alexander, M.
    Arla Foods Ingredients Group P/S, Denmark.
    Millqvist-Fureby, Anna
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation.
    Paulsson, M.
    Lund University, Sweden.
    Bergenståhl, B.
    Lund University, Sweden.
    Impact of surface properties on morphology of spray-dried milk serum protein/lactose systems2018In: International Dairy Journal, ISSN 0958-6946, E-ISSN 1879-0143, Vol. 85, p. 86-95Article in journal (Refereed)
    Abstract [en]

    This study investigated milk serum protein concentrate/lactose systems with varying ratios and how the morphology of the spray-dried particles of these systems could be described by the surface properties of the feed as well as the protein surface coverage of the particles. An extrapolation of the surface pressure of the feed to 0.3 s, the approximate time for molecular diffusion in an atomised droplet in the spray-dryer, showed a relationship with the particle morphology. At low protein concentrations (<1%), the particles were almost totally smooth. At higher protein concentrations (≥1%), the particles became dented and ridged, and these tended to become deeper and thicker as the protein concentration increased. It is suggested that the surface pressure of the feed at low protein concentrations is the most prominent surface property, whereas the modulus of elasticity seems to be the most prominent surface property for particle surface deformation at higher protein concentrations.

  • 6.
    Andersson, I. M.
    et al.
    Lund University, Sweden.
    Millqvist-Fureby, Anna
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation.
    Sommertune, Jens
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation.
    Alexander, M.
    Arla Foods Ingredients Group P/S, Denmark.
    Hellström, N.
    Lund University, Sweden.
    Glantz, Maria
    Lund University, Sweden.
    Paulsson, M.
    Lund University, Sweden.
    Bergenståhl, Björn
    Lund University, Sweden.
    Impact of protein surface coverage and layer thickness on rehydration characteristics of milk serum protein/lactose powder particles2019In: Colloids and Surfaces A: Physicochemical and Engineering Aspects, ISSN 0927-7757, E-ISSN 1873-4359, Vol. 561, p. 395-404Article in journal (Refereed)
    Abstract [en]

    Spray-dried powders were produced from milk serum protein concentrate and lactose in varying ratios, and the rehydration characteristics of the powders were evaluated. The dissolution rate was estimated with a flow-cell based technique, and the external and internal distribution of the powder components were evaluated with X-ray photoelectron spectroscopy and confocal Raman microscopy, respectively. The surface of the powder particles is more or less covered by a thin protein layer. A phase segregation between protein and lactose is observed in the interior of the particle resulting in a protein rich layer in the vicinity of the surface. However, the protein layer in the vicinity of the particle surface tends to become thinner as the bulk protein concentration increases in the powders (from 10 to 60% w/w). The time for the spontaneous imbibition to occur show a linear correlation with the protein surface coverage. The dissolution rate of powders containing 0.1% w/w protein is around 60 times faster than for a powder containing 1% w/w protein but the dissolution rate of powders containing 1% and 100% w/w differ only by a factor of 2. Thus, it is suggested that the outer protein layer becomes denser at the interface as the protein content increases in the powders, thereby causing poorer rehydration characteristics of the powders (especially for low protein concentrations 0.1–1% w/w). This insight has relevance for the formulation of whey protein powders with improved rehydration characteristics. © 2018 Elsevier B.V.

  • 7.
    Anheden, Marie
    et al.
    RISE - Research Institutes of Sweden, Bioeconomy.
    Uhlin, Anders
    RISE - Research Institutes of Sweden, Bioeconomy.
    Wolf, Jens
    RISE - Research Institutes of Sweden, Bioeconomy.
    Hedberg, Martin
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation.
    Berg, Robert
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation.
    Ankner, Tobias
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation.
    Berglin, Niklas
    NiNa Innovation, Sweden; ÅF Industry, Sweden.
    von Schenck, Anna
    NiNa Innovation, Sweden; ÅF Industry, Sweden.
    Larsson, Anders L
    Valmet AB, Sweden.
    Guimaraes, Matheus
    Fibria, Sweden.
    Fiskerud, Maria
    Karlstad Airport, Sweden.
    Andersson, Stefan
    RISE - Research Institutes of Sweden, Bioeconomy.
    Value chain for production of bio-oil from kraft lignin for use as bio-jet fuel2017In: The 7th Nordic Wood Biorefinery Conference held in Stockholm, Sweden, 28-30 Mar. 2017: NWBC 2017, Stockholm: RISE Bioekonomi , 2017, p. 104-109Conference paper (Refereed)
    Abstract [en]

    The LignoJet project aimed to achieve an intermediate lignin-oil product miscible with fossil feedstock and with a significantly reduced oxygen content. A technical concept for production has been studied that involves combined catalysed depolymerisation and hydrodeoxygenation, so called hydrogenolytic depolymerisation, of kraft lignin. Kraft lignin was separated through membrane ultrafiltration from softwood and eucalyptus black liquor followed by precipitation through LignoBoost technology. A difference in lignin properties was observed between ultrafiltration of softwood and eucalyptus black liquor through 15 and 150kDa ceramic membranes. Lignin-oils with similar oxygen content were produced regardless of origin and fractionation technique. A lignin-oil with favourable properties as precursor for refinery integration for jet fuel production as produced in small-scale batch experiments using nickel-based catalyst. Stable pumpable oils with melting point of less than 25-50 deg C and with 20-30% lower oxygen content and aromatic content were obtained that would be suitable as jet fuel precursors. The estimated production cost was found to be competitive with that of other liquid biofuels, while additional revenues could potentially be achieved by also producing chemical and materials from suitable fractions of the lignin-oil.

  • 8.
    Badal Tejedor, Maria
    et al.
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation. KTH Royal Institute of Technology, Sweden.
    Nordgren, Niklas
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation.
    Schuleit, Michael
    Novartis Pharma AG, Switzerland.
    Millqvist-Fureby, Anna
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation.
    Rutland, Mark W.
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation. KTH Royal Institute of Technology, Sweden.
    AFM Colloidal Probe Measurements Implicate Capillary Condensation in Punch-Particle Surface Interactions during Tableting2017In: Langmuir, ISSN 0743-7463, E-ISSN 1520-5827, Vol. 33, no 46, p. 13180-13188Article in journal (Refereed)
    Abstract [en]

    Adhesion of the powders to the punches is a common issue during tableting. This phenomenon is known as sticking and affects the quality of the manufactured tablets. Defective tablets increase the cost of the manufacturing process. Thus, the ability to predict the tableting performance of the formulation blend before the process is scaled-up is important. The adhesive propensity of the powder to the tableting tools is mostly governed by the surface-surface adhesive interactions. Atomic force microscopy (AFM) colloidal probe is a surface characterization technique that allows the measurement of the adhesive interactions between two materials of interest. In this study, AFM steel colloidal probe measurements were performed on ibuprofen, MCC (microcrystalline cellulose), α-lactose monohydrate, and spray-dried lactose particles as an approach to modeling the punch-particle surface interactions during tableting. The excipients (lactose and MCC) showed constant, small, attractive, and adhesive forces toward the steel surface after a repeated number of contacts. In comparison, ibuprofen displayed a much larger attractive and adhesive interaction increasing over time both in magnitude and in jump-in/jump-out separation distance. The type of interaction acting on the excipient-steel interface can be related to a van der Waals force, which is relatively weak and short-ranged. By contrast, the ibuprofen-steel interaction is described by a capillary force profile. Even though ibuprofen is not highly hydrophilic, the relatively smooth surfaces of the crystals allow "contact flooding" upon contact with the steel probe. Capillary forces increase because of the "harvesting" of moisture - due to the fast condensation kinetics - leaving a residual condensate that contributes to increase the interaction force after each consecutive contact. Local asperity contacts on the more hydrophilic surface of the excipients prevent the flooding of the contact zone, and there is no such adhesive effect under the same ambient conditions. The markedly different behavior detected by force measurements clearly shows the sticky and nonsticky propensity of the materials and allows a mechanistic description.

  • 9.
    Badal Tejedor, Maria
    et al.
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation. KTH Royal Institute of Technology, Sweden.
    Pazesh, Samaneh
    Uppsala University, Sweden.
    Nordgren, Niklas
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation.
    Schuleit, Micheal
    Novartis Pharma AG, Switzerland.
    Rutland, Mark W.
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation. KTH Royal Institute of Technology, Sweden.
    Alderborn, Göran
    Uppsala University, Sweden.
    Millqvist-Fureby, Anna
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation.
    Milling induced amorphisation and recrystallization of α-lactose monohydrate2018In: International Journal of Pharmaceutics, ISSN 0378-5173, E-ISSN 1873-3476, Vol. 537, no 1-2, p. 140-147Article in journal (Refereed)
    Abstract [en]

    Preprocessing of pharmaceutical powders is a common procedure to condition the materials for a better manufacturing performance. However, such operations may induce undesired material properties modifications when conditioning particle size through milling, for example. Modification of both surface and bulk material structure will change the material properties, thus affecting the processability of the powder. Hence it is essential to control the material transformations that occur during milling. Topographical and mechanical changes in surface properties can be a preliminary indication of further material transformations. Therefore a surface evaluation of the α-lactose monohydrate after short and prolonged milling times has been performed. Unprocessed α-lactose monohydrate and spray dried lactose were evaluated in parallel to the milled samples as reference examples of the crystalline and amorphous lactose structure. Morphological differences between unprocessed α-lactose, 1 h and 20 h milled lactose and spray dried lactose were detected from SEM and AFM images. Additionally, AFM was used to simultaneously characterize particle surface amorphicity by measuring energy dissipation. Extensive surface amorphicity was detected after 1 h of milling while prolonged milling times showed only a moderate particle surface amorphisation. Bulk material characterization performed with DSC indicated a partial amorphicity for the 1 h milled lactose and a fully amorphous thermal profile for the 20 h milled lactose. The temperature profiles however, were shifted somewhat in the comparison to the amorphous reference, particularly after extended milling, suggesting a different amorphous state compared to the spray-dried material. Water loss during milling was measured with TGA, showing lower water content for the lactose amorphized through milling compared to spray dried amorphous lactose. The combined results suggest a surface-bulk propagation of the amorphicity during milling in combination with a different amorphous structural conformation to that of the amorphous spray dried lactose. The hardened surface may be due to either surface crystallization of lactose or to formation of a low-water glass transition.

  • 10.
    Berg, Robert
    et al.
    RISE - Research Institutes of Sweden, Bioscience and Materials, Process och Pharmaceuticals Development.
    Bergman, Jan
    Karolinska Institute, Sweden.
    Synthesis of thieno[2,3-b]indole-2,3-diones and their ring expansions induced by diazomethane2017In: Tetrahedron, ISSN 0040-4020, E-ISSN 1464-5416, Vol. 73, no 38, p. 5654-5658Article in journal (Refereed)
    Abstract [en]

    Indole-2-thione 3 reacted quickly with oxalyl chloride to yield thieno[2,3-b]indole-2,3-dione 4 together with the isomer thiazolo[3,2-a]indole-2,3-dione 5. These thieno[2,3-b]indole-2,3diones underwent ring expansions when treated with diazomethane and e.g. thieno[2,3-b]indole-2,3-dione 4 gave the thiopyrano derivative 16, after two insertions.

  • 11.
    Bełdowski, Piotr
    et al.
    UTP University of Science and Technology, Poland.
    Weber, Piotr
    Gdansk University of Technology, Poland.
    Dedinaite, Andra
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation. KTH Royal Institute of Technology, Sweden.
    Claesson, Per M
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation. KTH Royal Institute of Technology, Sweden.
    Gadomski, Adam
    UTP University of Science and Technology, Poland.
    Physical crosslinking of hyaluronic acid in the presence of phospholipids in an aqueous nano-environment2018In: Soft Matter, ISSN 1744-683X, E-ISSN 1744-6848, Vol. 14, no 44, p. 8997-9004Article in journal (Refereed)
    Abstract [en]

    Hyaluronic acid and phospholipids are two components in the synovial joint cavity that contribute to joint lubrication synergistically. Molecular dynamics simulations were performed and hydrogen bonds in hyaluronic acid were analyzed to identify specific sites that are responsible for its physical cross-linking. Two molecular masses of hyaluronic acid, 10 kDa and 160 kDa, were considered. We use molecular dynamics simulations and the small world network approach to investigate dynamic couplings using a distance map applied to oxygen atoms in a chain of hyaluronic acid in the presence of phospholipids and water. The distance characterizing the coupling can be defined in various ways to bring out the most evident differences between various scenarios of the polymer chain conformation We show herein a physical distance understood as H-bond length and classes of these distances which are defined in a coarse-grained picture of the molecule. Simulation results indicate that addition of phospholipids has little influence on hyaluronic acid crosslinking. However, longer chains and addition of lipids promote appreciably long lasting (resilient) networks that may be of importance in biological systems. Specific sites for hydrogen bonding of phospholipids to hyaluronic acid have also been identified.

  • 12.
    Boge, Lukas
    et al.
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation. Chalmers University of Technology, Sweden.
    Browning, Kathryn
    University of Copenhagen, Denmark.
    Nordström, Randi
    Uppsala University, Sweden.
    Campana, Mario
    Rutherford Appleton Laboratory, UK.
    Damgaard, Liv
    University of Copenhagen, Denmark.
    Seth Caous, Josefin
    RISE - Research Institutes of Sweden, Bioscience and Materials, Chemistry and Materials.
    Hellsing, Maja
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation.
    Ringstad, Lovisa
    RISE - Research Institutes of Sweden, Bioscience and Materials, Chemistry and Materials.
    Andersson, Martin
    Chalmers University of Technology, Sweden.
    Peptide-Loaded Cubosomes Functioning as an Antimicrobial Unit against Escherichia coli2019In: ACS Applied Materials and Interfaces, ISSN 1944-8244, E-ISSN 1944-8252, Vol. 11, no 24, p. 21314-21322Article in journal (Refereed)
    Abstract [en]

    Dispersions of cubic liquid crystalline phases, also known as cubosomes, have shown great promise as delivery vehicles for a wide range of medicines. Due to their ordered structure, comprising alternating hydrophilic and hydrophobic domains, cubosomes possess unique delivery properties and compatibility with both water-soluble and -insoluble drugs. However, the drug delivery mechanism and cubosome interaction with human cells and bacteria are still poorly understood. Herein, we reveal how cubosomes loaded with the human cathelicidin antimicrobial peptide LL-37, a system with high bacteria-killing effect, interact with the bacterial membrane and provide new insights into the eradication mechanism. Combining the advanced experimental techniques neutron reflectivity and quartz crystal microbalance with dissipation monitoring, a mechanistic drug delivery model for LL-37-loaded cubosomes on bacterial mimicking bilayers was constructed. Moreover, the cubosome interaction with Escherichia coli was directly visualized using super-resolution laser scanning microscopy and cryogenic electron tomography. We could conclude that cubosomes loaded with LL-37 adsorbed and distorted bacterial membranes, providing evidence that the peptide-loaded cubosomes function as an antimicrobial unit.

  • 13.
    Boge, Lukas
    et al.
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation. Chalmers University of Technology, Sweden.
    Hallstensson, Karin
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation.
    Ringstad, Lovisa
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation.
    Johansson, Jenny
    RISE - Research Institutes of Sweden, Bioscience and Materials, Chemistry and Materials.
    Andersson, Therese
    RISE - Research Institutes of Sweden, Bioscience and Materials, Chemistry and Materials.
    Davoudi, Mina
    Lund University, Sweden.
    Larsson, Tomas
    RISE - Research Institutes of Sweden, Bioscience and Materials, Chemistry and Materials.
    Mahlapuu, Margit
    Promore Pharma AB, Sweden; University of Gothenburg, Sweden.
    Håkansson, Joakim
    RISE - Research Institutes of Sweden, Bioscience and Materials, Chemistry and Materials.
    Andersson, Martin
    Chalmers University of Technology, Sweden.
    Cubosomes for topical delivery of the antimicrobial peptide LL-372019In: European journal of pharmaceutics and biopharmaceutics, ISSN 0939-6411, E-ISSN 1873-3441, Vol. 134, p. 60-67Article in journal (Refereed)
    Abstract [en]

    In this study, the use of cubosomes for topical delivery of the antimicrobial peptide (AMP) LL-37 was investigated. Topical delivery of AMPs is of great interest for treatment of skin infections caused by bacteria, such as Staphylococcus aureus. AMP containing cubosomes were produced by three different preparation protocols and compared: (i) pre-loading, where LL-37 was incorporated into a liquid crystalline gel, which thereafter was dispersed into nanoparticles, (ii) post-loading, where LL-37 was let to adsorb onto pre-formed cubosomes, and (iii) hydrotrope-loading, where LL-37 was incorporated during the spontaneously formed cubosomes in an ethanol/glycerol monooleate mixture. Particle size and size distribution were analyzed using dynamic light scattering (DLS), liquid crystalline structure by small angle x-ray scattering (SAXS) and release of LL-37 by a fluorescamine assay. Proteolytic protection of LL-37 as well as bactericidal effect after enzyme exposure was investigated. The skin irritation potential of cubosomes was examined by an in vitro epidermis model. Finally, the bacterial killing property of the cubosomes was examined by an ex vivo pig skin wound infection model with Staphylococcus aureus. Data showed that a high loading of LL-37 induced formation of vesicles in case of cubosomes prepared by sonication (pre-loading). No release of LL-37 was observed from the cubosomes, indicating strong association of the peptide to the particles. Proteolysis studies showed that LL-37 was fully protected against enzymatic attacks while associated with the cubosomes, also denoting strong association of the peptide to the particles. As a consequence, bactericidal effect after enzyme exposure remained, compared to pure LL-37 which was subjected to proteolysis. No skin irritation potential of the cubosomes was found, thus enabling for topical administration. The ex vivo wound infection model showed that LL-37 in pre-loaded cubosomes killed bacteria most efficient.

  • 14.
    Boge, Lukas
    et al.
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation. Chalmers University of Technology, Sweden.
    Västberg, Amanda
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation.
    Umerska, Anita
    Université Bretagne Loire, France.
    Bysell, Helena
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation.
    Eriksson, Jonny
    Uppsala University, Sweden.
    Edwards, Katarina
    Uppsala University, Sweden.
    Millqvist-Fureby, Anna
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation.
    Andersson, Martin
    Chalmers University of Technology, Sweden.
    Freeze-dried and re-hydrated liquid crystalline nanoparticles stabilized with disaccharides for drug-delivery of the plectasin derivative AP114 antimicrobial peptide2018In: Journal of Colloid and Interface Science, ISSN 0021-9797, E-ISSN 1095-7103, Vol. 522, p. 126-135Article in journal (Refereed)
    Abstract [en]

    Liquid crystalline nanoparticles (LCNPs), e.g. cubosomes and hexosomes, are receiving more and more attraction as drug delivery vehicles. Dry powder formulation that forms LCNPs upon hydration can be advantageous to make new routes of administration accessible. In this work, we investigate use of three disaccharides (lactose, trehalose and sucrose) as protective matrices for glycerol monooleate based LCNP forming powders produced by freeze-drying. Phase behavior, particle size and size distributions at the different preparation steps were monitored by small angle x-ray scattering (SAXS) and dynamic light scattering (DLS). Particle appearance was imaged by cryogenic transmission electron microscopy (cryo-TEM). Moreover, the therapeutic relevant antimicrobial peptide AP114 (plectasin derivative) was incorporated in the formulations. Peptide encapsulation and release as well as in vitro antibacterial effect were investigated. Results showed that all freeze-dried powders did form particles with liquid crystalline structure upon hydration. However, a phase transition from the bicontinuous cubic Pn3m to the reversed hexagonal was observed, as a consequence of sugar addition and the freeze-drying procedure. Data indicates that trehalose is the preferred choice of lyo-protectant in order to maintain a mono-modal particle size distribution. In addition, antimicrobial activity of AP114-containing formulations was found to be highest for the formulation containing trehalose. The release kinetics of AP114 from the nanoparticles was strongly affected by the dimensions of the hexagonal phase. Larger dimension of the hexagonal phase, significantly improved the release of AP114 and antimicrobial activity of the formulation.

  • 15.
    Both, E M
    et al.
    Wageningen University and Research, The Netherlands.
    Nuzzo, Marine
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation.
    Millqvist-Fureby, Anna
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation.
    Boom, R M
    Wageningen University and Research, The Netherlands.
    Schutyser, M A I
    Wageningen University and Research, The Netherlands.
    Morphology development during single droplet drying of mixed component formulations and milk2018In: Food Research International, ISSN 0963-9969, E-ISSN 1873-7145, Vol. 109, p. 448-454, article id S0963-9969(18)30328-4Article in journal (Refereed)
    Abstract [en]

    We report on the influence of selected components and their mixtures on the development of the morphology during drying of single droplets and extend the results to the morphology of whole milk powder particles. Sessile single droplet drying and acoustic levitation methods were employed to study single droplet drying. The influence of carbohydrates (lactose and maltodextrin DE12) and proteins (micellar casein or whey protein) on morphology development is very different, since upon concentration protein systems will jam and undergo a colloidal glass transition, whereas carbohydrate systems will gradually increase in viscosity as a consequence of the concentration. Whey protein gives relatively rigid shells due to jamming of the "hard sphere" proteins, while casein micelles behave as "soft spheres" that can deform after jamming, which gives flexibility to the shell during drying. The influence of the carbohydrates on the final morphology was found much larger than the influence of the proteins. Caseins influenced morphology only in mixtures with lactose at higher concentrations due to its high voluminosity. Similar observations were done for whole milk, where fat appeared to have no influence. With maltodextrin the influence of the casein was again observed in the shape and smoothness of wrinkles. Both sessile and levitated droplet drying methods provide a similar and consistent view on morphology development.

  • 16.
    Brobbey, Kofi
    et al.
    Åbo Akademi University, Finland.
    Haapanen, Janne
    Tampere University of Technology, Finland.
    Mäkelä, Jyrki
    Tampere University of Technology, Finland.
    Gunell, Marianne
    University of Turku, Finland.
    Eerola, Erkki
    University of Turku, Finland.
    Rosqvist, Emil
    Åbo Akademi University, Finland.
    Peltonen, Jouko
    Åbo Akademi University, Finland.
    Saarinen, Jarkko
    University of Eastern Finland, Finland.
    Tuominen, Mirkko
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation.
    Toivakka, Martti
    Åbo Akademi University, Finland.
    Effect of plasma coating on antibacterial activity of silver nanoparticles2019In: Thin Solid Films, ISSN 0040-6090, E-ISSN 1879-2731, Vol. 672, p. 75-82Article in journal (Refereed)
    Abstract [en]

    Silver nanoparticles (NPs) are known to provide antimicrobial properties for surfaces. However, there are environmental concerns due to reports of toxicity after exposure to the environment during or after end-use. Immobilizing silver NPs to the surface of substrates could ensure that particles are readily available for antibacterial activity with limited environmental exposure. A plasma coating on top of silver NPs could improve the adhesion of NPs to a substrate, but it could also impede the release of silver NPs completely. Furthermore, silver has been shown to require direct contact to demonstrate antibacterial activity. This study demonstrates immobilization of silver NPs with plasma coating onto a surface while maintaining its antibacterial properties. Silver NPs are simultaneously synthesized and deposited onto a surface with liquid flame spray aerosol technique followed by hexamethyldisiloxane plasma coating to immobilize the NPs. Atomic force microscope scratch testing is used to demonstrate improved nanoparticle adhesion. Antibacterial activity against gram-negative Escherichia coli is maintained even for plasma coating thicknesses of 195 nm. NP adhesion to the surface is significantly improved. Gram-positive Staphylococcus aureus was found be resistant to all the plasma-coated samples. The results show promise of using plasma coating technology for limiting NP exposure to environment.

  • 17.
    Brobbey, Kofi
    et al.
    Abo Akademi, Finland.
    Haapanen, Janne
    Tampere University of Technology, Finland.
    Tuominen, Mikko
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation.
    Mäkelä, Jyrki
    Tampere University of Technology, Finland.
    Gunell, Marianne
    University of Turku, Finland.
    Eerola, Erkki
    University of Turku, Finland.
    Saarinen, Jarkko
    University of Eastern Finland, Finland.
    Toivakka, Martti
    Abo Akademi, Finland.
    High-speed production of antibacterial fabrics using liquid flame spray2019In: Textile research journal, ISSN 0040-5175, E-ISSN 1746-7748Article in journal (Refereed)
    Abstract [en]

    Healthcare associated infections (HAIs) are known as one of the major problems of the modern healthcare system, which result in additional cost and mortality. It has also been shown that pathogenic bacteria are mostly transferred via surfaces in healthcare settings. Therefore, antibacterial surfaces, which include fabrics and textiles, can be used in a healthcare environment to reduce the transfer of pathogenic bacteria, hence reducing HAIs. Silver nanoparticles have been shown to have broad spectrum antibacterial properties, and therefore they have been incorporated into fabrics to provide antibacterial functionality. Liquid flame spray (LFS) nanoparticle synthesis allows nanoparticles to be produced and deposited on surfaces at speeds up to and beyond 300 m/min. Herein, LFS is used to deposit silver nanoparticles onto two fabrics that are commonly used in the hospital environment with the aim of producing antibacterial fabrics. A thin plasma coating on top of the fabrics after silver deposition is used to improve nanoparticle adhesion. Fabrics coated with silver nanoparticles demonstrated antibacterial properties against Escherichia coli. Nanoparticle imaging and surface chemical characterization are performed using scanning electron microscopy and X-ray photoelectron spectroscopy. The highlights of this research are as follows: • high-speed synthesis and deposition of silver nanoparticles on fabrics; • plasma coating onto fabrics with silver nanoparticles; • antibacterial fabrics for potential use in healthcare environments. © The Author(s) 2019.

  • 18.
    Claesson, Per M.
    et al.
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation. KTH Royal Institute of Technology, Sweden.
    Dobryden, Illia
    KTH Royal Institute of Technology, Sweden.
    Li, Gen
    KTH Royal Institute of Technology, Sweden.
    He, Yunjian
    KTH Royal Institute of Technology, Sweden.
    Huang, Hui
    KTH Royal Institute of Technology, Sweden.
    Thorén, Per-Anders
    KTH Royal Institute of Technology, Sweden.
    Haviland, David B.
    From force curves to surface nanomechanical properties2017In: Physical Chemistry, Chemical Physics - PCCP, ISSN 1463-9076, E-ISSN 1463-9084, Vol. 19, no 35, p. 23642-23657Article in journal (Refereed)
    Abstract [en]

    Surface science, which spans the fields of chemistry, physics, biology and materials science, requires information to be obtained on the local properties and property variations across a surface. This has resulted in the development of different scanning probe methods that allow the measurement of local chemical composition and local electrical and mechanical properties. These techniques have led to rapid advancement in fundamental science with applications in areas such as composite materials, corrosion protection and wear resistance. In this perspective article, we focussed on the branch of scanning probe methods that allows the determination of surface nanomechanical properties. We discussed some different AFM-based modes that were used for these measurements and provided illustrative examples of the type of information that could be obtained. We also discussed some of the difficulties encountered during such studies.

  • 19.
    Costa, Carolina
    et al.
    Mid Sweden University, Sweden.
    Medronho, Bruno
    Mid Sweden University, Sweden; University of Algarve, Portugal.
    Filipe, Alexandra
    University of Algarve, Portugal.
    Mira, Isabel
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation.
    Lindman, Björn
    Mid Sweden University, Sweden.
    Edlund, Håkan
    Mid Sweden University, Sweden.
    Norgren, Magnus
    Mid Sweden University, Sweden.
    Emulsion Formation and Stabilization by Biomolecules: The Leading Role of Cellulose.2019In: Polymers, ISSN 2073-4360, E-ISSN 2073-4360, Vol. 11, no 10, article id E1570Article in journal (Refereed)
    Abstract [en]

    Emulsion stabilization by native cellulose has been mainly hampered because of its insolubility in water. Chemical modification is normally needed to obtain water-soluble cellulose derivatives. These modified celluloses have been widely used for a range of applications by the food, cosmetic, pharmaceutic, paint and construction industries. In most cases, the modified celluloses are used as rheology modifiers (thickeners) or as emulsifying agents. In the last decade, the structural features of cellulose have been revisited, with particular focus on its structural anisotropy (amphiphilicity) and the molecular interactions leading to its resistance to dissolution. The amphiphilic behavior of native cellulose is evidenced by its capacity to adsorb at the interface between oil and aqueous solvent solutions, thus being capable of stabilizing emulsions. In this overview, the fundamentals of emulsion formation and stabilization by biomolecules are briefly revisited before different aspects around the emerging role of cellulose as emulsion stabilizer are addressed in detail. Particular focus is given to systems stabilized by native cellulose, either molecularly-dissolved or not (Pickering-like effect).

  • 20.
    Costa, Carolina
    et al.
    Mid Sweden University, Sweden.
    Mira, Isabel
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation.
    Benjamins, Jan-Willem
    RISE - Research Institutes of Sweden, Bioscience and Materials, Chemistry and Materials.
    Lindman, Björn
    Mid Sweden University, Sweden.
    Edlund, Håkan
    Mid Sweden University, Sweden.
    Norgren, Magnus
    Mid Sweden University, Sweden.
    Interfacial activity and emulsion stabilization of dissolved cellulose2019In: Journal of Molecular Liquids, ISSN 0167-7322, E-ISSN 1873-3166, Vol. 292, article id 111325Article in journal (Refereed)
    Abstract [en]

    Some aspects of the interfacial behavior of cellulose dissolved in an aqueous solvent were investigated. Cellulose was found to significantly decrease the interfacial tension (IFT) between paraffin oil and 85 wt% phosphoric acid aqueous solutions. This decrease was similar in magnitude to that displayed by non-ionic cellulose derivatives. Cellulose's interfacial activity indicated a significant amphiphilic character and that the interfacial activity of cellulose derivatives is not only related to the derivatization but inherent in the cellulose backbone. This finding suggests that cellulose would have the ability of stabilizing dispersions, like oil-in-water emulsions in a similar way as a large number of cellulose derivatives. In its molecularly dissolved state, cellulose proved to be able to stabilize emulsions of paraffin in the polar solvent on a short-term. However, long-term stability against drop-coalescence was possible to achieve by a slight change in the amphiphilicity of cellulose, effected by a slight increase in pH. These emulsions exhibited excellent stability against coalescence/oiling-off over a period of one year. Ageing of the cellulose solution before emulsification (resulting in molecular weight reduction) was found to favour the creation of smaller droplets.

  • 21.
    Dedinaite, Andra
    et al.
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation. KTH Royal Institute of Technology, Sweden.
    Claesson, Per M.
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation. KTH Royal Institute of Technology, Sweden.
    Synergies in lubrication2017In: Physical Chemistry, Chemical Physics - PCCP, ISSN 1463-9076, E-ISSN 1463-9084, Vol. 19, no 35, p. 23677-23689Article in journal (Refereed)
    Abstract [en]

    To slide surfaces against each other with application of a minimum force and minimum wear has been important since ancient times, and it remains equally important today. The use of oil-soluble lubricants is widely spread in technology, whereas living organisms have developed water-soluble lubricants to facilitate sliding motions. In this perspective article we focus on water-based lubrication in the boundary lubrication regime, and particularly lubrication synergies. This focus has, of course, found inspiration from the outstanding lubrication properties of synovial joints. It has ignited significant amount of research, mostly aimed at answering the question: Which molecule is the magic biolubricant? Different research groups have advocated different answers, and the debate has been intensive. In this article we argue that the question in itself is inappropriate. The relevant question is rather the following: How do molecules work in synergy to provide superior lubrication?

  • 22.
    Dobryden, Illia
    et al.
    KTH Royal Institute of Technology, Sweden.
    Cortes Ruiz, Maria
    City College of New York, US.
    Zhang, Xuwei
    University of Montreal, Canada.
    Dedinaite, Andra
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation. KTH Royal Institute of Technology, Sweden.
    Wieland, Floria
    Institute for Materials Research, Germany.
    Winnik, Francoise
    University of Helsinki, Finland.
    Claesson, Per M
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation. KTH Royal Institute of Technology, Sweden.
    Thermoresponsive Pentablock Copolymer on Silica: Temperature Effects on Adsorption, Surface Forces, and Friction2019In: Langmuir, ISSN 0743-7463, E-ISSN 1520-5827, Vol. 35, no 3, p. 653-661Article in journal (Refereed)
    Abstract [en]

    The adsorption of hydrophilic or amphiphilic multiblock copolymers provides a powerful means to produce well-defined "smart" surfaces, especially if one or several blocks are sensitive to external stimuli. We focus here on an A-B-A-B-A copolymer, where A is a cationic poly((3-acrylamido-propyl)-trimethylammonium chloride) (PAMPTMA) block containing 15 (end blocks) or 30 (middle block) repeat units and B is a neutral thermosensitive water-soluble poly(2-isopropyl-2-oxazoline) (PIPOZ) block with 50 repeat units. X-ray reflectivity and quartz crystal microbalance with dissipation monitoring were employed to study the adsorption of PAMPTMA15-PIPOZ50-PAMPTMA30-PIPOZ50-PAMPTMA15 on silica surfaces. The latter technique was employed at different temperatures up to 50 °C. Surface forces and friction between the two silica surfaces across aqueous pentablock copolymer solutions at different temperatures were determined with the atomic force microscopy colloidal probe force and friction measurements. The cationic pentablock copolymer was found to have a high affinity to the negatively charged silica surface, leading to a thin (2 nm) and rigid adsorbed layer. A steric force was encountered at a separation of around 3 nm from hard wall contact. A capillary condensation of a polymer-rich phase was observed at the cloud point of the solution. The friction forces were evaluated using Amontons' rule modified with an adhesion term.

  • 23.
    Dobryden, Illia
    et al.
    KTH Royal Institute of Technology, Sweden.
    Steponavičiu Tė, Medeina
    Vilnius University, Lithuania.
    Klimkevičius, Vaidas
    Vilnius University, Lithuania.
    Makuška, Ričardas
    Vilnius University, Lithuania.
    Dedinaite, Andra
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation. KTH Royal Institute of Technology, Sweden.
    Liu, Xiaoyan
    Shaanxi Normal University, China.
    Corkery, Robert W
    KTH Royal Institute of Technology, Sweden.
    Claesson, Per Martin
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation. KTH Royal Institute of Technology, Sweden.
    Bioinspired Adhesion Polymers: Wear Resistance of Adsorption Layers.2019In: Langmuir, ISSN 0743-7463, E-ISSN 1520-5827Article in journal (Refereed)
    Abstract [en]

    Mussel adhesive polymers owe their ability to strongly bind to a large variety of surfaces under water to their high content of 3,4-dihydroxy-l-phenylalanine (DOPA) groups and high positive charge. In this work, we use a set of statistical copolymers that contain medium-length poly(ethylene oxide) side chains that are anchored to the surface in three different ways: by means of (i) electrostatic forces, (ii) catechol groups (as in DOPA), and (iii) the combination of electrostatic forces and catechol groups. A nanotribological scanning probe method was utilized to evaluate the wear resistance of the formed layers as a function of normal load. It was found that the combined measurement of surface topography and stiffness provided an accurate assessment of the wear resistance of such thin layers. In particular, surface stiffness maps allowed us to identify the initiation of wear before a clear topographical wear scar was developed. Our data demonstrate that the molecular and abrasive wear resistance on silica surfaces depends on the anchoring mode and follows the order catechol groups combined with electrostatic forces > catechol groups alone > electrostatic forces alone. The devised methodology should be generally applicable for evaluating wear resistance or "robustness" of thin adsorbed layers on a variety of surfaces.

  • 24.
    Dural-Erem, Aysin
    et al.
    University of Borås, Sweden.
    Wessman, Per
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation.
    Husmark, Ulrika
    SCA Hygiene Products AB, Sweden.
    Nierstrasz, Vincent
    University of Borås, Sweden.
    Biocontrol of solid surfaces in hospitals using microbial-based wipes2019In: Textile research journal, ISSN 0040-5175, E-ISSN 1746-7748, Vol. 89, no 2, p. 216-222Article in journal (Refereed)
    Abstract [en]

    Hospital-acquired infections have become a major challenge which threaten the hospitalized patients’ safety. The presence of nosocomial pathogens is generally reported in connection with solid surfaces near patient environments. These surfaces become significant sources of transmission and lead most often to the contamination and cross-contamination of nosocomial pathogens to the patients and staff. This paper investigates strategies to apply beneficial bacteria on viscose-based nonwoven wipes and the viability of these beneficial bacteria on the wipes along with characterization of the physical properties of the wipes. Major findings include that it is possible to produce dry wipes which contain an adequate number of beneficial bacteria or spores. After these wipes are wetted, they can release a certain number of bacteria from the wetted wipes. These released beneficial bacteria can inhibit pathogens by growing and colonizing on the wiped surfaces.

  • 25. Edvinsson, Rolf Krister
    et al.
    Kantzer, Eike Nicolas
    Larsson, Per Fredrik Olmo
    Lake, Fredrik
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation.
    Ten Kate, Antoon Jacob Berend
    Process to Prepare Higher Ethylene Amines and Ethylene Amine Derivatives2017Patent (Other (popular science, discussion, etc.))
  • 26. Edvinsson, Rolf Krister
    et al.
    Kantzer, Eike Nicolas
    Larsson, Per Fredrik Olmo
    Lake, Fredrik
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation.
    Ten Kate, Antoon Jacob Berend
    Ehlers, Ina
    Process to Prepare Higher Ethylene Amines and Ethylene Amine Derivatives2018Patent (Other (popular science, discussion, etc.))
  • 27. Edvinsson, Rolf Krister
    et al.
    Kantzer, Eike Nicolas
    Larsson, Per Fredrik Olmo
    Lake, Fredrik
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation.
    Ten Kate, Antoon Jacob Berend
    Schröder, Ulf
    Malmberg, Johan Salman
    Process to Convert Cyclic Alkylene Ureas Into Their Corresponding Alkylene Amines2018Patent (Other (popular science, discussion, etc.))
  • 28.
    Eneborg, Alexander
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation. KTH Royal Institute of Technology, Sweden.
    Improvement and Characterization of Aqueous Graphene Dispersions2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Graphene has many outstanding properties which make it a prime candidate for new technology. At the current time it is very difficult and expensive to produce large sheets of graphene, but there are many applications where that is not necessary and smaller flakes of graphene can be used instead. A practical way of handling these graphene flakes is in a dispersion, especially a water-based dispersion have many benefits. Such a stable dispersion of functionalized graphene is produced, improved, and characterized in this project. An aqueous system that was developed in two previous M.Sc. theses, each determining a suitable graphene powder and stabilizer, was used as a starting point with the main purpose being to improve the yield. The method used to produce these dispersions can be described as sonicating graphene powder in a solution of water and stabilizer followed by centrifuging to remove un-dispersed graphene particles. Experiments were carried out examining the possibility of dispersing those previously undispersed graphene flakes, combining the stabilizer with several surfactants, optimizing the centrifuge speed and time, refining the sonication procedure with longer exposure time and cooling, narrowing the size-distribution of the original stabilizer through ultrafiltration, and removing excessive unbound stabilizer through ultrafiltration. Samples were characterized with UV-vis, SEM, TGA, Electrophoretic light scattering, and Laser diffraction spectroscopy. It was discovered that the yield from the graphene powder was heavily dependent on sonication time and centrifugation conditions. The gain from increasing sonication time showed that most, if not all, of the un-dispersed graphene flakes previously considered lost could in fact be dispersed. In an industrial setting any un-dispersed flakes could simply be added to the next batch. Reducing the centrifugation speed as well as time increased the concentration of graphene to more than twice as high, and that gain comes solely from the larger graphene flakes. Thusly the previous problem with a low yield was shown to have been caused by too little sonication and too much centrifugation. The particle size analysis did show a small reduction in flake size as the sonication time was increased, but when those dispersions were characterized in SEM they all formed even films with no discernable difference between them. Purifying the scaled up dispersions by removing excess stabilizer through ultrafiltration was performed to three different degrees, 0 %, 50 % and 95 %, for a total of three dispersions of 100ml. All three dispersions were shown to be highly stable, with no apparent reduction in graphene concentration over 5 weeks and a zeta potential averaging below -50mV. The TGA results reinforce the UV-vis results, proving that the purification worked as intended.

  • 29.
    Eriksson, Mimmi
    et al.
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation. KTH Royal Institute of Technology, Sweden.
    Claesson, Per Martin
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation. KTH Royal Institute of Technology, Sweden.
    Järn, Mikael
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation.
    Tuominen, Mikko
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation.
    Wallqvist, Viveca
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation.
    Schoelkopf, Joachim
    Omya International AG, Switzerland.
    Gane, Patrick A C
    Aalto University, Finland.
    Swerin, Agne
    KTH Royal Institute of Technology, Sweden.
    Wetting Transition on Liquid-Repellent Surfaces Probed by Surface Force Measurements and Confocal Imaging.2019In: Langmuir, ISSN 0743-7463, E-ISSN 1520-5827, Vol. 35, no 41, p. 13275-13285Article in journal (Refereed)
    Abstract [en]

    Superhydrophobic surfaces in the Cassie-Baxter wetting state retain an air layer at the surface which prevents liquid water from reaching into the porous surface structure. In this work we explore how addition of ethanol, which reduces the surface tension, influences the wetting properties of superhydrophobic and smooth hydrophobic surfaces. Wetting properties are measured by dynamic contact angles, and the air layer at the superhydrophobic surface is visualized by laser scanning confocal microscopy. Colloidal probe atomic force microscopy measurements between a hydrophobic microsphere and the macroscopic surfaces showed that the presence of ethanol strongly affects the interaction forces. When the macroscopic surface is superhydrophobic, attractive forces extending up to a few micrometers are observed on retraction in water and in 20 vol % ethanol, signifying the presence of a large and growing gas capillary. Submicrometer attractive forces are observed between the probe particle and a smooth hydrophobic surface, and in this case a smaller gas capillary is formed. Addition of ethanol results in markedly different effects between superhydrophobic and hydrophobic surfaces. In particular, we show that the receding contact angle on the superhydrophobic surface is of paramount importance for describing the interaction forces.

  • 30.
    Eriksson, Mimmi
    et al.
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation.
    Tuominen, Mikko
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation.
    Järn, Mikael
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation.
    Claesson, Per Martin
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation. KTH Royal Institute of Technology, Sweden.
    Wallqvist, Viveca
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation.
    Butt, Hans-Jürgen
    Max Planck Institute for Polymer Research, Germany.
    Vollmer, Doris
    Max Planck Institute for Polymer Research, Germany.
    Kappl, Michael
    Max Planck Institute for Polymer Research, Germany.
    Schoelkopf, Joachim
    Omya International AG, Switzerland.
    Gane, Patrick A C
    Omya International AG, Switzerland.
    Teisala, Hannu
    Aalto University, Finland.
    Swerin, Agne
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation.
    Direct Observation of Gas Meniscus Formation on a Superhydrophobic Surface2019In: ACS Nano, ISSN 1936-0851, E-ISSN 1936-086X, Vol. 13, no 2, p. 2246-2252Article in journal (Refereed)
    Abstract [en]

    The formation of a bridging gas meniscus via cavitation or nanobubbles is considered the most likely origin of the submicrometer long-range attractive forces measured between hydrophobic surfaces in aqueous solution. However, the dynamics of the formation and evolution of the gas meniscus is still under debate, in particular, in the presence of a thin air layer on a superhydrophobic surface. On superhydrophobic surfaces the range can even exceed 10 μm. Here, we report microscopic images of the formation and growth of a gas meniscus during force measurements between a superhydrophobic surface and a hydrophobic microsphere immersed in water. This is achieved by combining laser scanning confocal microscopy and colloidal probe atomic force microscopy. The configuration allows determination of the volume and shape of the meniscus, together with direct calculation of the Young-Laplace capillary pressure. The long-range attractive interactions acting on separation are due to meniscus formation and volume growth as air is transported from the surface layer.

  • 31.
    Falk, Julia
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation. Uppsala University, Sweden.
    Freeze-drying of protein pharmaceutical in vials with different character2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Freeze-drying of protein pharmaceuticals is a procedure frequently used to obtain stability of the active pharmaceutical ingredientduring distribution and storage. It can be performed in pre-filled syringes, with a lubricous coating of silicone on the inside, to enable the piston moving. The coating changes the environment potentially affecting the features of the freeze-dried cake since the wetting behavior and adhesion to the inner wall is affected.This project aimed to investigate the effect of the siliconization of the cakes. Three different formulations were freeze-dried in nonsiliconized (NS) and siliconized vials using different siliconization protocols. Analysis was done using differential scanning calorimetry (DSC), thermal gravimetric analysis (TGA),scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and an embedding method, intended to give information about the cake’s shrinkage, cracking and pore-structure. The water content in the bottom of the cakes was consistently higher than in the top, a difference decreasing over time. Increased surface hydrophobicity lead to increased shrinkage of the cake’s volume and a decrease in fogging. The bottom of the protein cake in the vial siliconized with a commercial silicone emulsion consisted of pores with regularly equal pore size and thick pore walls, a structure not seen in any other cake. All cakes in the silicone emulsion siliconized vials had lower water content than the cakes in the vials using the other siliconization method. The XPS-analysis showed that the cakes in the emulsion siliconized vials contained silicon, indicating an excess of silicone when siliconizing and/or an unstable coating.

  • 32.
    Filippov, Andrei
    et al.
    Luleå University of Technology, Sweden.
    Gnezdilov, Oleg I.
    Kazan Federal University, Russia.
    Hjalmarsson, Nicklas
    KTH Royal Institute of Technology, Sweden.
    Antzutkin, Oleg N.
    Luleå University of Technology, Sweden.
    Glavatskih, Sergei B.
    KTH Royal Institute of Technology, Sweden; Ghent University, Belgium.
    Furó, István
    KTH Royal Institute of Technology, Sweden.
    Rutland, Mark W.
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation. KTH Royal Institute of Technology, Sweden.
    Acceleration of diffusion in ethylammonium nitrate ionic liquid confined between parallel glass plates2017In: Physical Chemistry, Chemical Physics - PCCP, ISSN 1463-9076, E-ISSN 1463-9084, Vol. 19, no 38, p. 25853-25858Article in journal (Refereed)
    Abstract [en]

    Diffusion of EAN confined between polar glass plates separated by a few micrometers is higher by a factor of ca. 2 as compared to bulk values. Formation of a new phase, different to the bulk, was suggested. © the Owner Societies 2017.

  • 33.
    Gao, Jiajia
    et al.
    KTH Royal Institue of Technology, Sweden.
    Fischer, Andreas
    KTH Royal Institue of Technology, Sweden.
    Svensson, Per H
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation. KTH Royal Institue of Technology, Sweden.
    Kloo, Lars
    KTH Royal Institue of Technology, Sweden.
    Crystallography as forensic tool for understanding electrolyte degradation in dye-sensitized solar cells2017In: ChemistrySelect, Vol. 2, no 4, p. 1675-1680Article in journal (Refereed)
    Abstract [en]

    The precipitation of solid compounds from model electrolytes for liquid dye-sensitized solar cells has a story to tell regarding decomposition processes to be expected in such systems. Of course, the crystal lattice energy for a specific crystalline compounds plays a role in what compound that will eventually precipitate, but the compounds nevertheless serve as indicators for what type of processes that take place in the solar cell electrolytes upon ageing. From the compounds isolated in this study we learn that both ligand exchange processes, double-salt precipitation and oxidation are degradation processes that should not be overlooked when formulating efficient and stable electrolytes for this type of electrochemical system.

  • 34.
    Garg, Neeraj
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation.
    The thyroid hormone mimetic compound KB2115 lowers plasma LDL cholesterol and stimulates bile acid synthesis without cardiac effects in humans2008In: Proceedings of the National Academy of Sciences of the United States of America, ISSN 1091-6490, Vol. 105, no 2, p. 663-667, article id PNASA6Article in journal (Refereed)
  • 35.
    Ghorbani, Morteza
    et al.
    KTH Royal Institute of Technology, Sweden; Sabanci University, Turkey.
    Olofsson, Karl
    KTH Royal Institute of Technology, Sweden.
    Benjamins, Jan Willem
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation.
    Loskutova, Ksenia
    KTH Royal Institute of Technology, Sweden.
    Paulraj, Thomas
    KTH Royal Institute of Technology, Sweden.
    Wiklund, Martin
    Grishenkov, Dmitry
    KTH Royal Institute of Technology, Sweden.
    Svagan, Anna
    KTH Royal Institute of Technology, Sweden.
    Unravelling the Acoustic and Thermal Responses of Perfluorocarbon Liquid Droplets Stabilized with Cellulose Nanofibers2019In: Langmuir, ISSN 0743-7463, E-ISSN 1520-5827Article in journal (Refereed)
    Abstract [en]

    The attractive colloidal and physicochemical properties of cellulose nanofibers (CNFs) at interfaces have recently been exploited in the facile production of a number of environmentally benign materials, e.g. foams, emulsions, and capsules. Herein, these unique properties are exploited in a new type of CNF-stabilized perfluoropentane droplets produced via a straightforward and simple mixing protocol. Droplets with a comparatively narrow size distribution (ca. 1-5 μm in diameter) were fabricated, and their potential in the acoustic droplet vaporization process was evaluated. For this, the particle-stabilized droplets were assessed in three independent experimental examinations, namely temperature, acoustic, and ultrasonic standing wave tests. During the acoustic droplet vaporization (ADV) process, droplets were converted to gas-filled microbubbles, offering enhanced visualization by ultrasound. The acoustic pressure threshold of about 0.62 MPa was identified for the cellulose-stabilized droplets. A phase transition temperature of about 22 °C was observed, at which a significant fraction of larger droplets (above ca. 3 μm in diameter) were converted into bubbles, whereas a large part of the population of smaller droplets were stable up to higher temperatures (temperatures up to 45 °C tested). Moreover, under ultrasound standing wave conditions, droplets were relocated to antinodes demonstrating the behavior associated with the negative contrast particles. The combined results make the CNF-stabilized droplets interesting in cell-droplet interaction experiments and ultrasound imaging. 

  • 36.
    Haapanen, Janne
    et al.
    Tampere University of Technology, Finland.
    Aromaa, Mikko
    Tampere University of Technology, Finland.
    Teisala, Hannu
    Tampere University of Technology, Finland; Max Planck Institute for Polymer Research, Germany.
    Juuti, Paxton
    Tampere University of Technology, Finland.
    Tuominen, Mikko
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation. Tampere University of Technology, Finland.
    Sillanpaa, Markus
    Finnish Environment Institute, Finland.
    Stepien, Milena
    Abo Akademi University, Finland; AGH University of Science and Technology, Poland.
    Saarinen, Jarkko
    University of Eastern Finland, Finland.
    Toivakka, Martti
    Abo Akademi University, Finland.
    Kuusipalo, Jurkka
    Tampere University of Technology, Finland.
    Makela, Jyrki
    Tampere University of Technology, Finland.
    On the limit of superhydrophobicity: Defining the minimum amount of TiO2 nanoparticle coating2018In: Materials Research Express, ISSN 2053-1591, Vol. 6, no 3, article id 035004Article in journal (Refereed)
    Abstract [en]

    Fabrication of superhydrophobic surfaces in large scale has been in high interest for several years, also titanium oxide nanostructures having been applied for the purpose. Optimizing the amount and structure of the TiO2 material in the coating will play a key role when considering upscaling. Here, we take a look at fabricating the superhydrophobic surface in a one-step roll-to-roll pilot scale process by depositing TiO2 nanoparticles from a Liquid Flame Spray onto a moving paperboard substrate. In order to find the minimum amount of nanomaterial still sufficient for creating superhydrophobicity, we varied nanoparticle production rate, flame distance from the substrate and line speed. Since the deposited amount of material sideways from the flame path was seen to decrease gradually, spatial analysis enabled us to consistently determine the minimum amount of TiO2 nanoparticles on the substrate needed to achieve superhydrophobicity. Amount as low as 20-30 mg m-2 of TiO2 nanoparticles was observed to be sufficient. The scanning electron microscopy revealed that at this amount, the surface was covered with nanoparticles only partially, but still sufficiently to create a hierarchical structure to affect wetting significantly. Based on XPS analysis, it became apparent that TiO2 gathers hydrocarbons on the surface to develop the surface chemistry towards hydrophobic, but below the critical amount of TiO2 nanoparticles, the chemistry could not enable superhydrophobicity anymore. While varying the deposited amount of TiO2, besides the local spatial variance of the coating amount, also the overall yield was studied. Within the text matrix, a yield up to 44% was achieved. In conclusion, superhydrophobicity was achieved at all tested line speeds (50 to 300 m min-1), even if the amount of TiO2 varied significantly (20 to 230 mg m-2). 

  • 37.
    Halamoda-Kenzaoui, Blanka
    et al.
    European Commission Joint Research Centre, Italy.
    Baconnier, Simon
    Université Grenoble Alpes, France.
    Bastogne, Thierry
    CNRS Université de Lorraine, France.
    Bazile, Didier
    CMC External Innovation, France.
    Boisseau, Patrick
    Université Grenoble Alpes, France.
    Borchard, Gerrit
    Université de Genève, Switzerland.
    Borgos, Sven Even
    SINTEF, Norway.
    Calzolai, Luigi
    European Commission Joint Research Centre, Italy.
    Cederbrant, Karin
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation.
    Di Felice, Gabriella
    National Center for Drug Research and Evaluation, Italy.
    Di Francesco, Tiziana
    Université de Genève, Switzerland.
    Dobrovolskaia, Marina A
    Frederick National Laboratory for Cancer Research, USA.
    Gaspar, Rogério
    University of Lisbon, Portugal.
    Gracia, Belén
    Agencia Española de Medicamentos y Productos Sanitarios, Spain.
    Hackley, Vincent A
    NIST National Institute of Standards and Technology, USA.
    Leyens, Lada
    Swissmedic, Switzerland.
    Liptrott, Neill
    University of Liverpool, UK.
    Park, Margriet
    RIVM National Institute for Public Health and the Environment, The Netherlands.
    Patri, Anil
    U.S. Food & Drug Administration, USA.
    Roebben, Gert
    European Commission Joint Research Centre, Belgium.
    Roesslein, Matthias
    EMPA, Switzerland.
    Thürmer, Rene
    Federal Institute for Drugs and Medical Devices, Germany.
    Urbán, Patricia
    European Commission Joint Research Centre, Italy.
    Zuang, Valérie
    European Commission Joint Research Centre, Italy.
    Bremer-Hoffmann, Susanne
    European Commission Joint Research Centre, Belgium.
    Bridging communities in the field of nanomedicine2019In: Regulatory toxicology and pharmacology, ISSN 0273-2300, E-ISSN 1096-0295, Vol. 106, p. 187-196, article id S0273-2300(19)30110-2Article in journal (Refereed)
    Abstract [en]

    An early dialogue between nanomedicine developers and regulatory authorities are of utmost importance to anticipate quality and safety requirements for these innovative health products. In order to stimulate interactions between the various communities involved in a translation of nanomedicines to clinical applications, the European Commission's Joint Research Centre hosted a workshop titled "Bridging communities in the field of Nanomedicine" in Ispra/Italy on the 27th -28th September 2017. Experts from regulatory bodies, research institutions and industry came together to discuss the next generation of nanomedicines and their needs to obtain regulatory approval. The workshop participants came up with recommendations highlighting methodological gaps that should be addressed in ongoing projects addressing the regulatory science of nanomedicines. In addition, individual opinions of experts relevant to progress of the regulatory science in the field of nanomedicine were summarised in the format of a survey.

  • 38.
    Harra, Juha
    et al.
    Tampere University of Technology, Finland.
    Tuominen, Mikko
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation.
    Juuti, Paxton
    Tampere University of Technology, Finland.
    Rissler, Jenny
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation. Lund University, Sweden.
    Koivuluoto, Heli
    Tampere University of Technology, Finland.
    Haapanen, Janne
    Tampere University of Technology, Finland.
    Niemelä-Anttonen, Hanna
    Tampere University of Technology, Finland.
    Stenroos, Christian
    Tampere University of Technology, Finland.
    Teisala, Hannu
    Tampere University of Technology, Finland.
    Lahti, Johanna
    Tampere University of Technology, Finland.
    Kuusipalo, Jurkka
    Tampere University of Technology, Finland.
    Vuoristo, Petri
    Tampere University of Technology, Finland.
    Mäkelä, Jyrki M.
    Tampere University of Technology, Finland.
    Characteristics of nFOG, an aerosol-based wet thin film coating technique2018In: JCT Research, ISSN 1547-0091, E-ISSN 2168-8028, Vol. 15, no 3, p. 623-632Article in journal (Refereed)
    Abstract [en]

    An atmospheric pressure aerosol-based wet thin film coating technique called the nFOG is characterized and applied in polymer film coatings. In the nFOG, a fog of droplets is formed by two air-assist atomizers oriented toward each other inside a deposition chamber. The droplets settle gravitationally and deposit on a substrate, forming a wet film. In this study, the continuous deposition mode of the nFOG is explored. We determined the size distribution of water droplets inside the chamber in a wide side range of 0.1–100 µm and on the substrate using aerosol measurement instruments and optical microscopy, respectively. The droplet size distribution was found to be bimodal with droplets of approximately 30–50 µm contributing the most to the mass of the formed wet film. The complementary measurement methods allow us to estimate the role of different droplet deposition mechanisms. The obtained results suggest that the deposition velocity of the droplets is lower than the calculated terminal settling velocity, likely due to the flow fields inside the chamber. Furthermore, the mass flux of the droplets onto the substrate is determined to be in the order of 1 g/m3s, corresponding to a wet film growth rate of 1 µm/s. Finally, the nFOG technique is demonstrated by preparing polymer films with thicknesses in the range of approximately 0.1–20 µm.

  • 39.
    He, Yunjuan
    et al.
    KTH Royal Institute of Technology, Sweden.
    Boluk, Yaman
    University of Alberta, Canada.
    Pan, Jinshan
    KTH Royal Institute of Technology, Sweden.
    Ahniyaz, Anwar
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation.
    Deltin, Tomas
    PTE Coatings AB, Sweden.
    Claesson, Per M.
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation. KTH Royal Institute of Technology, Sweden.
    Corrosion protective properties of cellulose nanocrystals reinforced waterborne acrylate-based composite coating2019In: Corrosion Science, ISSN 0010-938X, E-ISSN 1879-0496, Vol. 155, p. 186-194Article in journal (Refereed)
    Abstract [en]

    The present investigation highlights corrosion protection of carbon steel by a waterborne acrylate-based matrix coating, with and without reinforcement by cellulose nanocrystals, by using electrochemical impedance spectroscopy in 0.1 M NaCl solution over a period of 35 days. Interactions between cellulose nanocrystals and the matrix coating were demonstrated by Fourier transform infrared spectroscopy. The results show that both coatings have high barrier performance but different protective characteristics during long-term exposure. The differences can be attributed to the reinforcement effect of cellulose nanocrystals caused by hydrogen bonding interactions between cellulose nanocrystals and the matrix coating.

  • 40.
    He, Yunjuan
    et al.
    KTH Royal Institute of Technology, Sweden.
    Dobryden, Illia
    KTH Royal Institute of Technology, Sweden.
    Pan, Jinshan
    KTH Royal Institute of Technology, Sweden.
    Ahniyaz, Anwar
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation.
    Deltin, Tomas
    PTE Coatings AB, Sweden.
    Corkery, Robert W.
    KTH Royal Institute of Technology, Sweden.
    Claesson, Per M.
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation. KTH Royal Institute of Technology, Sweden.
    Nano-scale mechanical and wear properties of a waterborne hydroxyacrylic-melamine anti-corrosion coating2018In: Applied Surface Science, ISSN 0169-4332, E-ISSN 1873-5584, Vol. 457, p. 548-558Article in journal (Refereed)
    Abstract [en]

    Corrosion protection is commonly achieved by applying a thin polymer coating on the metal surface. Many studies have been devoted to local events occurring at the metal surface leading to local or general corrosion. In contrast, changes occurring in the organic coating after exposure to corrosive conditions are much less studied. In this article we outline how changes in the coating itself due to curing conditions, environmental and erosion effects can be investigated at the nanometer scale, and discuss how such changes would affect its corrosion protection performance. We focus on a waterborne hydroxyacrylic-melamine coating, showing high corrosion protection performance for carbon steel during long-term (≈35 days) exposure to 0.1 M NaCl solution. The effect of curing time on the conversion of the crosslinking reaction within the coating was evaluated by fourier transform infrared spectroscopy (FTIR); the wetting properties of the cured films were investigated by contact angle measurement, and the corrosion resistance was studied by electrochemical impedance spectroscopy (EIS). In particular, coating nanomechanical and wear properties before and after exposure to 0.1 M NaCl, were evaluated by atomic force microscopy (AFM). Fiber-like surface features were observed after exposure, which are suggested to arise due to diffusion of monomers or low molecular weight polymers to the surface. This may give rise to local weakening of the coating, leading to local corrosion after even longer exposure times. We also find a direct correlation between the stick-slip spacing during shearing and plastic deformation induced in the surface layer, giving rise to topographical ripple structures on the nanometer length scale.

  • 41.
    Hellsing, Maja
    et al.
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation.
    Rennie, Adrian
    Uppsala University, Sweden.
    Rodal, Michael
    Biolin Scientific AB, Sweden.
    Höök, Fredrik
    Chalmers University of Technology, Sweden.
    Charged polystyrene nanoparticles near a SiO2/water interface2019In: Langmuir, ISSN 0743-7463, E-ISSN 1520-5827, Vol. 35, no 1, p. 222-228Article in journal (Refereed)
    Abstract [en]

    Quartz crystal microbalance with dissipation (QCM-D) monitoring is traditionally used to investigate adsorption processes at liquid-solid interfaces but has also been applied increasingly to characterize the viscoelastic properties of complex liquids. Here, we contribute new insights to the latter field by using QCM-D to investigate the structure near an interface and high-frequency viscoelastic properties of charge stabilized polystyrene particles (radius 37 nm) dispersed in pure water. The study reveals changes with increasing ionic-strength from the crystalline order at low salt concentration to that with a less-structured particle distribution at high ionic strength. Replacing pure water with an aqueous particle dispersion is due to an increased mass load expected to give rise to a decrease in frequency, f. In the present work increases in both f and dissipation, D, were observed on exchanging pure water for the particle dispersion at low ionic strength. However, the QCM-D data are still well-represented by a viscoelastic Voigt model, with the viscosity increasing from 1.0 to 1.3 mPa s as the particle volume fraction changed from 0.005 to 0.07. This increase is higher than predicted for dilute dispersions according to Einstein’s equation for the viscosity of non-interacting hard spheres particles in liquids but can be explained by the charge repulsion between the particles giving rise to a higher effective volume fraction. It is also concluded that the polystyrene particles did not adhere to the solid surface but rather were separated by a layer of pure dispersion medium. The QCM-D response was successfully represented using a viscoelastic Kelvin-Voigt model, from which it was concluded that the thickness of the Newtonian dispersion medium layer was of the order of the particle-particle bulk separation, in the range 50 to 250 nm and was observed to decrease with both particle concentration and with addition of salt. Similar anomalous frequency and dissipation responses have been seen previously for colloidal systems containing weakly adherent colloidal particles and bacteria and in these cases interpreted in terms of coupled resonators. We here demonstrate that surface attachment is not required for such phenomena to occur, but that a viscoelastic liquid separated from the oscillating surface by a thin Newtonian layer can give rise to very similar responses.

  • 42.
    Hjalmarsson, Nicklas
    et al.
    KTH Royal Institute of Technology, Sweden.
    Bergendal, Erik
    KTH Royal Institute of Technology, Sweden.
    Wang, Yong-Lei
    KTH Royal Institute of Technology, Sweden.
    Munavirov, Bulat
    KTH Royal Institute of Technology, Sweden.
    Wallinder, Daniel
    Attana AB, Sweden .
    Glavatskih, Sergei
    Ghent University, Belgium; KTH Royal Institute of Technology, Sweden.
    Aastrup, Teodor
    Attana AB, Sweden .
    Atkin, Rob
    University of Western Australia, Australia.
    Furó, István
    KTH Royal Institute of Technology, Sweden.
    Rutland, Mark W.
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation. KTH Royal Institute of Technology, Sweden.
    Electro-Responsive Surface Composition and Kinetics of an Ionic Liquid in a Polar Oil.2019In: Langmuir, ISSN 0743-7463, E-ISSN 1520-5827Article in journal (Refereed)
    Abstract [en]

    The quartz crystal microbalance (QCM) has been used to study how the interfacial layer of an ionic liquid dissolved in a polar oil at low weight percentages responds to changes in applied potential. The changes in surface composition at the QCM gold surface depend on both the magnitude and sign of the applied potential. The time-resolved response indicates that the relaxation kinetics are limited by the diffusion of ions in the interfacial region and not in the bulk, since there is no concentration dependence. The measured mass changes cannot be explained only in terms of simple ion exchange; the relative molecular volumes of the ions and the density changes in response to ion exclusion must be considered. The relaxation behavior of the potential between the electrodes upon disconnecting the applied potential is more complex than that observed for pure ionic liquids, but a measure of the surface charge can be extracted from the exponential decay when the rapid initial potential drop is accounted for. The adsorbed film at the gold surface consists predominantly of ionic liquid despite the low concentration, which is unsurprising given the surtactant-like structures of (some of) the ionic liquid ions. Changes in response to potential correspond to changes in the relative numbers of cations and anions, rather than a change in the oil composition. No evidence for an electric field induced change in viscosity is observed. This work shows conclusively that electric potentials can be used to control the surface composition, even in an oil-based system, and paves the way for other ion solvent studies.

  • 43.
    Ivarsson, Magnus
    et al.
    University of Southern Denmark, Denmark; Swedish Museum of Natural History, Sweden.
    Skogby, Henrik
    Swedish Museum of Natural History, Sweden.
    Phichaikamjornwut, Bongkot
    Srinakharinwirot University, Thailand.
    Bengtson, Stefan
    Swedish Museum of Natural History, Sweden.
    Siljeström, Sandra
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation.
    Ounchanum, Prayote
    Chiang Mai University, Thailand.
    Boonsoong, Apichet
    Chiang Mai University, Thailand.
    Kruachanta, Mingkhwan
    Chiang Mai University, Thailand.
    Marone, Federica
    Paul Scherrer Institute, Switzerland.
    Belivanova, Veneta
    Swedish Museum of Natural History, Sweden.
    Holmström, Sara
    Stockholm University, Sweden.
    Intricate tunnels in garnets from soils and river sediments in Thailand - Possible endolithic microborings2018In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 13, no 8, article id e0200351Article in journal (Refereed)
    Abstract [en]

    Garnets from disparate geographical environments and origins such as oxidized soils and river sediments in Thailand host intricate systems of microsized tunnels that significantly decrease the quality and value of the garnets as gems. The origin of such tunneling has previously been attributed to abiotic processes. Here we present physical and chemical remains of endolithic microorganisms within the tunnels and discuss a probable biological origin of the tunnels. Extensive investigations with synchrotron-radiation X-ray tomographic microscopy (SRXTM) reveal morphological indications of biogenicity that further support a euendolithic interpretation. We suggest that the production of the tunnels was initiated by a combination of abiotic and biological processes, and that at later stages biological processes came to dominate. In environments such as river sediments and oxidized soils garnets are among the few remaining sources of bio-available Fe2+, thus it is likely that microbially mediated boring of the garnets has trophic reasons. Whatever the reason for garnet boring, the tunnel system represents a new endolithic habitat in a hard silicate mineral otherwise known to be resistant to abrasion and chemical attack.

  • 44.
    Jakobsson, Jonas K.F.
    et al.
    Lund University, Sweden.
    Aaltonen, H. Laura
    Lund University, Sweden.
    Nicklasson, Hanna
    Lund University, Sweden.
    Gudmundsson, Anders
    Lund University, Sweden.
    Rissler, Jenny
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation. Lund University, Sweden.
    Wollmer, Per E.
    Lund University, Sweden.
    Löndahl, Jakob
    Lund University, Sweden.
    Altered deposition of inhaled nanoparticles in subjects with chronic obstructive pulmonary disease2018In: BMC Pulmonary Medicine, ISSN 1471-2466, E-ISSN 1471-2466, Vol. 18, no 1, article id 129Article in journal (Refereed)
    Abstract [en]

    Background: Respiratory tract deposition of airborne particles is a key link to understand their health impact. Experimental data are limited for vulnerable groups such as individuals with respiratory diseases. The aim of this study is to investigate the differences in lung deposition of nanoparticles in the distal lung for healthy subjects and subjects with respiratory disease. Methods: Lung deposition of nanoparticles (50 and 100 nm) was measured after a 10 s breath-hold for three groups: healthy never-smoking subjects (n = 17), asymptomatic (active and former) smokers (n = 15) and subjects with chronic obstructive pulmonary disease (n = 16). Measurements were made at 1300 mL and 1800 mL volumetric lung depth. Each subject also underwent conventional lung function tests, including post bronchodilator FEV1, VC, and diffusing capacity for carbon monoxide, DL,CO. Patients with previously diagnosed respiratory disease underwent a CT-scan of the lungs. Particle lung deposition fraction, was compared between the groups and with conventional lung function tests. Results: We found that the deposition fraction was significantly lower for subjects with emphysema compared to the other subjects (p = 0.001-0.01), but no significant differences were found between healthy never-smokers and smokers. Furthermore, the particle deposition correlated with pulmonary function tests, FEV1%Pred (p &lt; 0.05), FEV1/VC%Pred (p &lt; 0.01) and DL,CO (p &lt; 0.0005) when all subjects were included. Furthermore, for subjects with emphysema, deposition fraction correlated strongly with DL,CO (Pearson's r = 0.80-0.85, p &lt; 0.002) while this correlation was not found within the other groups. Conclusions: Lower deposition fraction was observed for emphysematous subjects and this can be explained by enlarged distal airspaces in the lungs. As expected, deposition increases for smaller particles and deeper inhalation. The observed results have implications for exposure assessment of air pollution and dosimetry of aerosol-based drug delivery of nanoparticles.

  • 45.
    Janosik, Tomasz
    et al.
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation.
    Rannug, Agneta
    Karolinska Institutet, Sweden.
    Rannug, Ulf
    Stockholm University, Sweden.
    Wahlström, Niklas
    MagleChemoswed, Sweden.
    Slätt, Johnny
    KTH Royal Institute of Technology, Sweden.
    Bergman, Jan
    Karolinska Institutet, Sweden.
    Chemistry and Properties of Indolocarbazoles2018In: Chemical Reviews, ISSN 0009-2665, E-ISSN 1520-6890, Vol. 118, no 18, p. 9058-9128Article in journal (Refereed)
    Abstract [en]

    The indolocarbazoles are an important class of nitrogen heterocycles which has evolved significantly in recent years, with numerous studies focusing on their diverse biological effects, or targeting new materials with potential applications in organic electronics. This review aims at providing a broad survey of the chemistry and properties of indolocarbazoles from an interdisciplinary point of view, with particular emphasis on practical synthetic aspects, as well as certain topics which have not been previously accounted for in detail, such as the occurrence, formation, biological activities, and metabolism of indolo[3,2- b]carbazoles. The literature of the past decade forms the basis of the text, which is further supplemented with older key references.

  • 46. Kantzer, Eike Nicolas
    et al.
    Lake, Fredrik
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation.
    Ten Kate, Antoon Jacob Berend
    Raaijmakers, Michiel Jozef Thomas
    Veneman, Rens
    Ehlers, Ina
    Sarning, Michael Bertil Einar
    Van Dam, Hendrik
    Edvinsson, Krister
    Process for Manufacturing Hydroxethyl Ethylene Amines2018Patent (Other (popular science, discussion, etc.))
  • 47. Kantzer, Eike Nicolas
    et al.
    Lake, Fredrik
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation.
    Ten Kate, Antoon Jacob Berend
    Raaijmakers, Michiel Jozef Thomas
    Veneman, Rens
    Ehlers, Ina
    Sarning, Michael Bertil Einar
    Van Dam, Henrdik
    Edvinsson, Rolf Krister
    Adrian Meredith, Jenny Valborg Therese
    Process for Manufacturing Ethylene Amines2018Patent (Other (popular science, discussion, etc.))
  • 48.
    Karlsson, Mikael
    et al.
    Chalmers University of Technology, Sweden.
    Abbas, Zareen
    University of Gothenburg, Sweden.
    Bordes, Romain
    Chalmers University of Technology, Sweden.
    Cao, Yu
    Chalmers University of Technology, Sweden.
    Larsson, Anders
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation.
    Rolland, Antonin
    Chalmers University of Technology, Sweden.
    Taylor, Phil
    AkzoNobel Decorative Paints, UK.
    Steenari, Britt-Marie
    Chalmers University of Technology, Sweden.
    Surface properties of recycled titanium oxide recovered from paint waste2018In: Progress in organic coatings, ISSN 0300-9440, E-ISSN 1873-331X, Vol. 125, p. 279-286Article in journal (Refereed)
    Abstract [en]

    Aluminium oxide coated rutile pigment was extracted from a paint matrix by means of a thermal recycling process. The objective was to investigate the effect of the recycling process on the surface properties of the pigment. The pigment was analysed using powder x-ray diffraction (XRD), surface area measurements (BET), laser diffraction for particle size analysis and X-ray photoelectron spectroscopy (XPS) before and after the recycling process. Investigations on the zeta potential and the surface charge were performed as well. It was concluded that the rutile crystalline core and the aluminium oxide coating of the pigment were still intact after the recycling process. The particle size distribution of the recycled pigment was slightly broader compared to the virgin pigment. The measured magnitude in zeta potential of the recycled pigment was lower than for the virgin pigment. This difference is thought to be caused by alteration in the surface hydroxyl concentration. Surface charge titrations showed differences between the virgin and the recycled pigment at alkaline pH and at low salt concentrations.

  • 49.
    Karlsson, Mikael C. F.
    et al.
    Chalmers University of Technology, Sweden.
    Abbas, Zareen
    University of Gothenburg, Sweden.
    Bordes, Romain
    Chalmers University of Technology, Sweden.
    Cao, Yu
    Chalmers University of Technology, Sweden.
    Larsson, Anders
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation.
    Taylor, Phil
    AkzoNobel Decorative Paints, UK.
    Steenari, Britt-Marie
    Chalmers University of Technology, Sweden.
    Characterisation of silicon, zirconium and aluminium coated titanium dioxide pigments recovered from paint waste2019In: Dyes and pigments, ISSN 0143-7208, E-ISSN 1873-3743, Vol. 162, p. 145-152Article in journal (Refereed)
    Abstract [en]

    Titanium dioxide (TiO2) is the major white pigment used by the paint industry. However, the production of TiO2 is associated with a high carbon footprint. An alternative source of pigment could be created by developing a method to recover it from waste paint. In this paper two rutile pigments with different surface treatments were recovered from paint by a thermal recycling process. The pigments were analysed using powder x-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), surface area measurements (BET), laser diffraction for particle size analysis and zeta potential measurements before and after the recycling process. It was concluded that the rutile cores of both pigments were intact and there were no major changes in particle size distribution or surface charge for either pigment induced by the recycling process. However, XPS and zeta potential measurements showed that the surface coating of the pigments can be more or less degraded depending on the chemical nature, which might imply the need for further re-coating after-treatment. Another option would be to find another application for the pigment where the quality and function of the coating is of less importance.

  • 50.
    Karlsson, Mikael
    et al.
    Chalmers University of Technology, Sweden.
    Álvarez-Asencio, Ruben
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation.
    Bordes, Romain
    Chalmers University of Technology, Sweden.
    Larsson, Anders
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation.
    Taylor, Phil
    AkzoNobel Decorative Paints, UK.
    Steenari, Britt-Marie
    Chalmers University of Technology, Sweden.
    Characterization of paint formulated using secondary TiO2 pigments recovered from waste paint2019In: JCT Research, ISSN 1547-0091, E-ISSN 2168-8028, Vol. 16, no 2, p. 607-614Article in journal (Refereed)
    Abstract [en]

    The paint industry is continuously striving to reduce its environmental impact, especially when it comes to the major virgin white pigment, titanium dioxide (TiO2). In this work, recycled TiO2 pigment was used in a paint formulation as a replacement for pigment made from virgin raw materials. The paint was evaluated based on pH, Stormer and ICI viscosities, gloss, hiding power, and color characteristics. The paint films were also characterized by LVSEM–EDS, AFM, and profilometry. The most significant difference between a paint based on recycled pigments and a paint based on virgin pigments was the agglomeration of pigment particles which gave a reduction in gloss and a rougher surface of the dried paint film based on recycled pigment, and it could be concluded that the recycled pigment could not be used without accepting a small decrease in paint quality. This points toward two main directions: (1) the use of recycled pigment in applications with less demand on surface finish and gloss, such as ceiling paints, and (2) that further work on formulation should be carried out with the recycled pigment as for any other new pigment introduced in a paint formulation to optimize its performance. © 2018, The Author(s).

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