title: Poly(N-vinyl-pyrrolidone)-block-poly(D,L-lactide) as polymeric emulsifier for the preparation of biodegradable nanoparticles.
abstract: Poly(D,L-lactide) (PDLLA) amphiphilic block copolymers were employed as emulsifiers in the preparation of PDLLA nanoparticles by an oil/water emulsion solvent evaporation technique. The surface-active properties of poly(N-vinyl-pyrrolidone)-block-poly(D,L-lactide) (PVP-b-PDLLA) toward the biphasic system were compared to those of polyethylene glycol(PEG)-b-PDLLA of similar composition. PVP-b-PDLLA was found to be a suitable emulsifier for dichloromethane/water emulsions, yielding narrowly distributed nanoparticles (<250 nm) surrounded by a hydrophilic PVP corona. PEG-b-PDLLA, however, was only effective in producing appropriately sized nanoparticles when dichloromethane was replaced with ethyl acetate. Furthermore, the lyoprotectant properties of PVP allowed the freeze-dried nanoparticles to recover their initial size following reconstitution, while PEG-coated nanoparticles could not be redispersed following lyophilization. Two poorly water-soluble drugs, that is, paclitaxel and etoposide, were efficiently loaded into PVP-decorated PDLLA nanoparticles. The entrapment efficiency of etoposide was significantly enhanced by adding MgCl2 to the aqueous phase. It was found that the nanoparticles released the drugs progressively over several days in vitro. The obtained experimental results were corroborated with the theoretical compatibility between a given drug, polymer, and solvent, predicted by total solubility parameters.
authors: Canada Research Chair in Drug Delivery, Faculty of Pharmacy, University of Montreal, C.P. 6128, Succ. Centre-Ville, Montreal, Quebec H3C 3J7, Canada.
authors: Geneviève
authors: G
authors: Gaucher
authors: Monika
authors: M
authors: Poreba
authors: François
authors: F
authors: Ravenelle
authors: Jean-Christophe
authors: JC
authors: Leroux
mesh_terms: D000085:Acetates / Q000737:chemistry; D000972:Antineoplastic Agents, Phytogenic / Q000737:chemistry; D002626:Chemistry, Pharmaceutical; D004339:Drug Compounding; D045703:Emulsifying Agents / Q000737:chemistry*; D005047:Etoposide / Q000737:chemistry; D005612:Freeze Drying; D007700:Kinetics; D007773:Lactates / Q000737:chemistry*; D015636:Magnesium Chloride / Q000737:chemistry; D008752:Methylene Chloride / Q000737:chemistry; D053758:Nanoparticles; D017239:Paclitaxel / Q000737:chemistry; D011092:Polyethylene Glycols / Q000737:chemistry*; D011137:Polystyrenes / Q000737:chemistry*; D011145:Polyvinyls / Q000737:chemistry*; D012995:Solubility; D012997:Solvents / Q000737:chemistry; D013678:Technology, Pharmaceutical / Q000379:methods; D014867:Water / Q000737:chemistry
chemical_list: D000085:Acetates; D000972:Antineoplastic Agents, Phytogenic; D045703:Emulsifying Agents; D007773:Lactates; D011137:Polystyrenes; D011145:Polyvinyls; D012997:Solvents; C522357:poly(N-vinyl-pyrrolidone)-block-poly(D,L-lactide); C088513:poly(lactic acid-ethylene glycol); D015636:Magnesium Chloride; D014867:Water; D011092:Polyethylene Glycols; D008752:Methylene Chloride; D005047:Etoposide; C007650:ethyl acetate; D017239:Paclitaxel