Linked Life Data

16128237

Source:http://linkedlifedata.com/resource/pubmed/id/16128237

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
8
pubmed:dateCreated
2005-8-30
pubmed:abstractText
The ingress of water and Kokubo simulated body fluid (SBF) into poly(2-hydroxyethyl methacrylate) (PHEMA), and its co-polymers with tetrahydrofurduryl methacrylate (THFMA), loaded with either one of two model drugs, vitamin B12 or aspirin, was studied by mass uptake over the temperature range 298-318 K. The polymers were studied as cylinders and were loaded with either 5 wt% or 10 wt% of the drugs. From DSC studies it was observed that vitamin B12 behaved as a physical cross-linker restricting chain segmental mobility, and so had a small anti-plasticisation effect on PHEMA and the co-polymers rich in HEMA, but almost no effect on the Tg of co-polymers rich in THFMA. On the other hand, aspirin exhibited a plasticising effect on PHEMA and the co-polymers. All of the polymers were found to absorb water and SBF according to a Fickian diffusion mechanism. The polymers were all found to swell to a greater extent in SBF than in water, which was attributed to the presence of Tris buffer in the SBF. The sorptions of the two penetrants were found to follow Fickian kinetics in all cases and the diffusion coefficients at 310 K for SBF were found to be smaller than those for water, except for the polymers containing aspirin where the diffusion coefficients were higher than for the other systems. For example, for sorption into PHEMA the diffusion coefficient for water was 1.41 x 10(-11) m2/s and for SBF was 0.79 x 10(-11) m2/s, but in the presence of 5 wt% aspirin the corresponding values were 1.27 x 10(-11) m2/s and 1.25 x 10(-11) m2/s, respectively. The corresponding values for PHEMA loaded with 5 wt% B12 were 1.25 x 10(-11) m2/s and 0.74 x 10(-11) m2/s, respectively.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
0920-5063
pubmed:author
pubmed:issnType
Print
pubmed:volume
16
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1047-61
pubmed:dateRevised
2008-2-20
pubmed:meshHeading
pubmed:year
2005
pubmed:articleTitle
Mass uptake study of the diffusion of water and SBF into poly(2-hydroxyethyl methacrylate-co-tetrahydrofurfuryl methacrylate) containing aspirin or vitamin B12.
pubmed:affiliation
Polymer Materials and Radiation Group, Department of Chemistry, The University of Queensland, Brisbane, QLD 4072, Australia.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't