Linked Life Data

8961156

Source:http://linkedlifedata.com/resource/pubmed/id/8961156

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
11
pubmed:dateCreated
1997-3-13
pubmed:abstractText
The purpose of this study was to compare the various methods available to separate non-encapsulated drug from large unilamellar liposomes (LUV). Multilamellar liposomes (MLV) were prepared by thin film hydration using distearoylphosphatidylcholine:cholesterol (2:1 molar ratio). MLVs were passed through a 0.2 micron polycarbonate membrane using an extruder to prepare LUVs. Particle size of liposome preparations was characterized using a submicron particle-size analyser. The non-encapsulated drug was separated by: filtering through Centrifree tubes; passing through gel (Sepharose-4B and Sephadex G-25M); passing through minicolumn; ficoll density gradient; protamine aggregation; or dialysis. The dialysis method was found to be unsuitable for separation of non-encapsulated drug due to equilibration of encapsulated drug as the free drug was dialyzed. The upper limit for lipid concentration was 5 mg mL-1 using the Centrifree method. Separation using gel chromatography led to dilution of liposome preparation. Minicolumn and density gradient techniques did not lead to sample dilution, however the minicolumn method was tedious. The time required for separation of liposomes by protamine aggregation was longer for neutral liposomes. Thus it was concluded that the Centrifree was the fastest method to estimate encapsulation; the density gradient method was ideal to separate non-encapsulated drug; and protamine aggregation was the least expensive method to estimate encapsulation efficiency.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0022-3573
pubmed:author
pubmed:issnType
Print
pubmed:volume
48
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1112-5
pubmed:dateRevised
2004-11-17
pubmed:meshHeading
pubmed:year
1996
pubmed:articleTitle
Comparative study of separation of non-encapsulated drug from unilamellar liposomes by various methods.
pubmed:affiliation
Department of Pharmacal Sciences, School of Pharmacy, Auburn University, AL 36849-5503, USA.
pubmed:publicationType
Journal Article