Linked Life Data

15899561

Source:http://linkedlifedata.com/resource/pubmed/id/15899561

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2005-7-4
pubmed:abstractText
The aim of this work was to assess the influence of various formulation parameters on the incorporation of a poorly water-soluble crystalline drug into nanoparticles. For this purpose, the influence of the polymer (polylactic acid, polysebacic acid terminated with lithocholic acid, and polysebacic acid-co-lithocholic acid) as well as the effect of the dispersion medium (aqueous phases at different temperatures, saline medium and ethanol) on the encapsulation was investigated. 3H-labelled drug was used in order to determine the loading efficiency by liquid scintillation counting. The solubility of the drug in the various polymer materials was assessed by differential scanning calorimetry (DSC). The solubility of the drug in the different dispersion media was then determined by gas chromatographic-mass spectrometric measurements. The highest loading ratios were obtained using poly (lactic acid) (PLA). However, the drug solubility in the polymers, determined by DSC analysis, cannot be considered as predictive for encapsulation efficiency. The study of the influence of the liquid outer phase showed that the encapsulation efficiency increased when the drug solubility in the dispersion medium (before acetone evaporation) decreased. These experiments made it possible to propose a mechanism to account for the leakage of the crystalline drug during the nanoprecipitation process. So, when acetone is eliminated by evaporation, the drug solubility in the dispersion medium decreases, leading to the formation of crystals. During nanoparticles storage, the crystals continue to grow, the nanoparticles serving as drug reservoirs. These findings highlight the importance of using a polymer with a specific affinity for the drug, and a dispersion medium with the lowest drug solubility to achieve an efficient encapsulation of a crystalline drug.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0378-5173
pubmed:author
pubmed:issnType
Print
pubmed:day
25
pubmed:volume
298
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
323-7
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2005
pubmed:articleTitle
Nanoencapsulation of a crystalline drug.
pubmed:affiliation
Faculty of Pharmacy, UMR 8612, University of Paris-Sud XI, 5, rue J.B Clément, 92296 Châtenay-Malabry, France.
pubmed:publicationType
Journal Article