Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Determination of interfacial amorphicity in functional powders
RISE - Research Institutes of Sweden (2017-2019), Bioscience and Materials, Chemistry and Materials. KTH Royal Institute of Technology, Sweden.ORCID iD: 0000-0001-5894-7123
RISE - Research Institutes of Sweden (2017-2019), Bioscience and Materials, Chemistry and Materials.ORCID iD: 0000-0003-4472-5102
Novartis Pharma AG, Switzerland.
Uppsala University, Sweden.
Show others and affiliations
2017 (English)In: Langmuir, ISSN 0743-7463, E-ISSN 1520-5827, Vol. 33, no 4, p. 920-926Article in journal (Refereed) Published
Abstract [en]

The nature of the surfaces of particles of pharmaceutical ingredients, food powders, and polymers is a determining factor for their performance in for example tableting, powder handling, or mixing. Changes on the surface structure of the material will impact the flow properties, dissolution rate, and tabletability of the powder blend. For crystalline materials, surface amorphization is a phenomenon which is known to impact performance. Since it is important to measure and control the level of amorphicity, several characterization techniques are available to determine the bulk amorphous content of a processed material. The possibility of characterizing the degree of amorphicity at the surface, for example by studying the mechanical properties of the particles' surface at the nanoscale, is currently only offered by atomic force microscopy (AFM). The AFM PeakForce QNM technique has been used to measure the variation in energy dissipation (eV) at the surface of the particles which sheds light on the mechanical changes occurring as a result of amorphization or recrystallization events. Two novel approaches for the characterization of amorphicity are presented here. First, since particles are heterogeneous, we present a methodology to present the results of extensive QNM analysis of multiple particles in a coherent and easily interpreted manner, by studying cumulative distributions of dissipation data with respect to a threshold value which can be used to distinguish the crystalline and amorphous states. To exemplify the approach, which is generally applicable to any material, reference materials of purely crystalline α-lactose monohydrate and completely amorphous spray dried lactose particles were compared to a partially amorphized α-lactose monohydrate sample. Dissipation data are compared to evaluations of the lactose samples with conventional AFM and SEM showing significant topographical differences. Finally, the recrystallization of the surface amorphous regions in response to humidity was followed by studying the dissipation response of a well-defined surface region over time, which confirms both that dissipation measurement is a useful measure of surface amorphicity and that significant recrystallization occurs at the surface in response to humidity.

Place, publisher, year, edition, pages
2017. Vol. 33, no 4, p. 920-926
National Category
Chemical Sciences
Identifiers
URN: urn:nbn:se:ri:diva-28201DOI: 10.1021/acs.langmuir.6b03969Scopus ID: 2-s2.0-85011117083OAI: oai:DiVA.org:ri-28201DiVA, id: diva2:1086646
Available from: 2017-04-03 Created: 2017-04-03 Last updated: 2023-05-26Bibliographically approved

Open Access in DiVA

No full text in DiVA

Other links

Publisher's full textScopus

Authority records

Badal Tejedor, MariaNiklas, NordgrenMillqvist-Fureby, AnnaRutland, Mark W.

Search in DiVA

By author/editor
Badal Tejedor, MariaNiklas, NordgrenMillqvist-Fureby, AnnaRutland, Mark W.
By organisation
Chemistry and Materials
In the same journal
Langmuir
Chemical Sciences

Search outside of DiVA

GoogleGoogle Scholar

doi
urn-nbn

Altmetric score

doi
urn-nbn
Total: 230 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf