Linked Life Data

15710508

Source:http://linkedlifedata.com/resource/pubmed/id/15710508

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2005-2-15
pubmed:abstractText
In an attempt to achieve post-inhalation modulation of drug release rate, Bhavane et al. have recently proposed a microparticle agglomerate of nano-sized liposomal particles, with the agglomeration process consisting of chemical cross-linkages that are capable of cleavage [Bhavane et al. J. Cont. Rel 93 (2003) 15-28.]. There, the in vitro modulation of release from agglomerated liposomes encapsulating the antibiotic ciprofloxacin was demonstrated. However, the cleaving agents used in the previous studies are not acceptable for in vivo use. In the present work therefore, a new generation of in vivo compatible agglomerated liposomes has been developed. The release rate of encapsulated compounds from these carriers can be modulated by the addition of mild thiolytic cleaving agents such as cysteine. Specifically, an amino terminated PEG conjugate has been successfully synthesized, similar to the conjugate proposed by Zalipsky [Bioconjugate Chemistry, 10 (5) (1999) 703-707.]. This conjugate contains a dithiobenzyl urethane linkage between the lipid and the PEG, cleavable by the addition of cysteine. The amines at the distal ends of the PEG are used to cross-link the liposomes into agglomerates by the addition of a suitable cross-linking agent reactive towards amines. The cross-linkages were cleaved by cysteine at the DTB sites, resulting in changes in the size distribution of the agglomerates, as well as changes in the release rate of the encapsulated drug.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0168-3659
pubmed:author
pubmed:issnType
Print
pubmed:day
2
pubmed:volume
103
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
159-75
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2005
pubmed:articleTitle
Preparation of in vivo cleavable agglomerated liposomes suitable for modulated pulmonary drug delivery.
pubmed:affiliation
Department of Chemical Engineering, University of Houston, Houston, TX 77030, USA.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't