A Bochot1, E Fattal, A Gulik, G Couarraze, P Couvreur. 1. Laboratoire de Physico-Chimie, Pharmacotechnie, Biopharmacie, URA CNRS 1218, Faculté de Pharmacie, Châtenay-Malabry, France.
Abstract
PURPOSE: The main goal of this study was to develop an ocular controlled release formulation of a model oligonucleotide (pdT16), contained within liposomes dispersed within a thermosensitive gel composed by poloxamer 407. METHODS: The influence of the poloxamer concentration 2% or 27% on the stability of the liposomes (PC: CHOL and PC: CHOL: PEG-DSPE) was investigated. The in vitro release profiles of pdT16 from various poloxamer formulations (free pdT16 dispersed within 20% and 27% poloxamer gels, pdT16 encapsulated within liposomes dispersed within 20% and 27% poloxamer gels) were realized using a membrane-free release model. RESULTS: The dispersion of liposomes within a dilute 2% poloxamer solution resulted in a great leakage of pdT16 from liposomes. However, the destabilization effect of poloxamer was reduced when higher concentration (27%) was used. Poloxamer dissolution was found to control the release process of pdT16, whereas the dispersion of liposomes within 27% poloxamer gel was shown to slow down the diffusion of pdT16 out from the gel. CONCLUSIONS: The dispersion of liposomes within a 27% poloxamer gel presented an interesting system to control the release of a model oligonucleotide compare to a simple gel.
PURPOSE: The main goal of this study was to develop an ocular controlled release formulation of a model oligonucleotide (pdT16), contained within liposomes dispersed within a thermosensitive gel composed by poloxamer 407. METHODS: The influence of the poloxamer concentration 2% or 27% on the stability of the liposomes (PC: CHOL and PC: CHOL: PEG-DSPE) was investigated. The in vitro release profiles of pdT16 from various poloxamer formulations (free pdT16 dispersed within 20% and 27% poloxamer gels, pdT16 encapsulated within liposomes dispersed within 20% and 27% poloxamer gels) were realized using a membrane-free release model. RESULTS: The dispersion of liposomes within a dilute 2% poloxamer solution resulted in a great leakage of pdT16 from liposomes. However, the destabilization effect of poloxamer was reduced when higher concentration (27%) was used. Poloxamer dissolution was found to control the release process of pdT16, whereas the dispersion of liposomes within 27% poloxamer gel was shown to slow down the diffusion of pdT16 out from the gel. CONCLUSIONS: The dispersion of liposomes within a 27% poloxamer gel presented an interesting system to control the release of a model oligonucleotide compare to a simple gel.
Authors: V P Torchilin; V G Omelyanenko; M I Papisov; A A Bogdanov; V S Trubetskoy; J N Herron; C A Gentry Journal: Biochim Biophys Acta Date: 1994-10-12
Authors: Sasa Andjelić; Jenny Yuan; Dennis D Jamiolkowski; Robert Diluccio; Rao Bezwada; Hua Zhang; Jovan Mijović Journal: Pharm Res Date: 2006-02-10 Impact factor: 4.200
Authors: Ana L Gomes dos Santos; Amélie Bochot; Nicolas Tsapis; Franck Artzner; Riad Antoine Bejjani; Brigitte Thillaye-Goldenberg; Yvonne de Kozak; Elias Fattal; Francine Behar-Cohen Journal: Pharm Res Date: 2006-04-06 Impact factor: 4.200