Linked Life Data

11943392

Source:http://linkedlifedata.com/resource/pubmed/id/11943392

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1-3
pubmed:dateCreated
2002-4-10
pubmed:abstractText
Oral absorption of the antihyperglycaemic agent metformin (MF x HCl) is confined to the upper part of the intestine, therefore controlled-release oral formulations of this drug should ensure a complete release during transit from stomach to jejunum. Compressed matrix tablets based on pH-sensitive poly(ethylene oxide) (PEO)-Eudragit L100 (EUD L) compounds have shown in vitro a compliance with the above requirement. The polymer compounds were prepared by a coevaporation process. The release pattern of MF x HCl from matrices depended on the PEO-EUD L ratio in the coevaporate. The 1:1 (w/w) ratio was unable to control MF x HCl release in simulated gastric fluid (SGF, pH 1.2), because the matrix material was excessively hydrophilic. Nevertheless, the release rate in SGF could be modulated by increasing the EUD L fraction in the coevaporate. With a PEO (M(w), 400 kDa)-EUD L (1:2, w/w) ratio the percent dose released in 2 h to SGF, where the coevaporate was insoluble, was around 23 or 50% with 10 or 20% loading dose. The release was then completed within the successive 2 h of elution with simulated jejunal fluid (SJF, pH 6.8) where EUD L and the coevaporate gradually dissolved. Release in SGF was controlled by matrix swelling and/or drug diffusion in matrix, whereas matrix dissolution controlled release in SJF. The unique release-controlling properties of the polymer compounds were due to PEO-EUD L macromolecular interactions. Matrices show promise of a gradual and complete release of MF x HCl from stomach to jejunum, unaffected by gastric pH fluctuations. This mode of administration might allow the use of lower therapeutic doses compared to existing immediate- or sustained-release products, thus minimising side effects.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0168-3659
pubmed:author
pubmed:issnType
Print
pubmed:day
23
pubmed:volume
80
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
119-28
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2002
pubmed:articleTitle
In vitro evaluation of a system for pH-controlled peroral delivery of metformin.
pubmed:affiliation
Department of Bioorganic Chemistry and Biopharmaceutics, University of Pisa, Via Bonanno 33, 56126 Pisa, Italy. giadic@farm.unipi.it
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't