Linked Life Data

15451519

Source:http://linkedlifedata.com/resource/pubmed/id/15451519

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2004-9-28
pubmed:abstractText
Reversible hetero-stereoselective complexes were obtained by mixing acetonitrile solutions of enantiomeric D-poly(lactic acid) (d-PLA) and leuprolide, an L-configured nonapeptide LHRH analogue. The complex spontaneously aggregated and precipitated in high yields (95%) from acetonitrile solutions, forming uniform, porous microparticles with a mean unweighed particle size of 1.7 microm. The complexation of L-configured peptide occurred only with D-PLA, and not with L-PLA or racemic D,L-PLA. Various factors affecting the release pattern of leuprolide from the hetero-stereocomplexes were investigated. Complexes with D-PLA of low molecular weight (< 10,000 Da) displayed lower release rates of leuprolide than high molecular weight D-PLA (> 50,000 Da). Changing the leuprolide: D-PLA ratio from 1:50 to 1:10 (w/w) in the stereocomplex, resulted in a faster release of leuprolide. Similarly, the release rate of leuprolide was twice as fast when adding poly(ethylene glycol) to the acetonitrile complexation solution. Leuprolide was released from most of the formulations in a first order pattern, with only a small burst release during the first 24 h. Addition of water to the complexation solution significantly increased the initial release of the peptide. Low testosterone levels for over 25 days were observed in an in vivo release study of leuprolide from a hetero-stereocomplex formulation, monitoring testosterone levels in the blood of rats after sub cutaneous injection.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0939-6411
pubmed:author
pubmed:issnType
Print
pubmed:volume
58
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
461-9
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2004
pubmed:articleTitle
Hetero-stereocomplexes of D-poly(lactic acid) and the LHRH analogue leuprolide. Application in controlled release.
pubmed:affiliation
Department of Medicinal Chemistry and Natural Products, Faculty of Medicine, School of Pharmacy, Hebrew University of Jerusalem, Jerusalem, Israel.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't