Linked Life Data

12906337

Source:http://linkedlifedata.com/resource/pubmed/id/12906337

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
7
pubmed:dateCreated
2003-8-8
pubmed:abstractText
The objective of this study was to evaluate the utility of mixtures among oppositely charged dextran derivatives as constituents of a controlled release microsphere. Carboxymethyldextran (CMD) and dextran sulfate (DS) were used as polyanions, and [2-(diethylamino) ethyl] dextran (EA) and [2-hydroxypropyltrimethylammonium] dextran (CDC) as polycations. The microspheres consisting of hydrophilic and hydrophobic polymers were prepared by emulsion-solvent evaporation method. The mixtures, CMD/EA, CMD/CDC, DS/EA, and DS/CDC, were used as hydrophilic polymers, because they can interact with each other to form polyion complexes for the improvement of sustained-release performances. Cellulose acetate butyrate and theophylline were used as a model hydrophobic polymer and a model drug, respectively. The yield of microspheres was excellent (more than 95%). According to observation, by scanning election microscopy (SEM) microspheres were spherical with a rough surface. The in vitro drug release from microspheres was examined in the JP XIV first fluid, pH 1.2, and second fluid, p H 6.8, at 37 degrees C, and 100 rpm. In the DS/CDC system, drug release was depressed by formation of a polyion complex and not affected by pH of dissolution medium. The release rate was modulated by the ratio of hydrophilic and hydrophobic matrix. This particulate system, in which the polyion complex matrix is strengthened by a hydrophobic polymer, is a promising formulation for drug delivery.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0363-9045
pubmed:author
pubmed:issnType
Print
pubmed:volume
29
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
795-804
pubmed:meshHeading
pubmed:year
2003
pubmed:articleTitle
Release profiles of theophylline from microspheres consisting of dextran derivatives and cellulose acetate butyrate: effect of polyion complex formation.
pubmed:affiliation
Pharmaceutical Department, Tokyo Women's Medical University Daini Hospital, Arakawa-ku, Tokyo, Japan. myph@dnh.twmu.ac.jp
pubmed:publicationType
Journal Article, Evaluation Studies