Linked Life Data

19543608

Source:http://linkedlifedata.com/resource/pubmed/id/19543608

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
7
pubmed:dateCreated
2009-6-22
pubmed:abstractText
We use scanning-transmission X-ray microspectroscopy (STXM) for in situ characterization of the physicochemical changes in air-filled poly(vinyl alcohol) (PVA) based microbubbles upon soft X-ray irradiation. The microbubbles were illuminated directly in aqueous suspension with 520 eV X-rays and a continuous shrinkage of the particles with an illumination time/radiation dose was observed. Utilizing the intrinsic absorption properties of the species and the high spatial resolution of the STXM, the modifications of the particles' structure were simultaneously recognized. A thorough characterization of the microbubble volume, membrane thickness and absorption coefficient was performed by quantitative fitting of the radial transmittance profiles of the targeted microbubbles. Apart from the observed volume contraction, there was no significant change in the shell thickness. The chemical changes in the membranes were clarified via C K-edge near-edge X-ray absorption fine structure (NEXAFS) spectroscopy. It was revealed that the observed structural alterations go along with a continuous degradation of the PVA network associated with formation of carbonyl- and carboxyl-containing species as well as an increased content of unsaturated bonds.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
1463-9076
pubmed:author
pubmed:issnType
Print
pubmed:day
21
pubmed:volume
11
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1098-104
pubmed:meshHeading
pubmed:year
2009
pubmed:articleTitle
Soft X-ray induced modifications of PVA-based microbubbles in aqueous environment: a microspectroscopy study.
pubmed:affiliation
Friedrich-Alexander Universität Erlangen-Nürnberg, Department Chemie und Pharmazie, Egerlandstrasse 3, D-91058 Erlangen, Germany. george.tzvetkov@psi.ch
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't