title: Study of emulsion stabilization by graft copolymers using the optical analyzer Turbiscan.
abstract: Oil-in-water nanoemulsions were prepared using a series of synthetic graft copolymers with a backbone of dextran (DEX) and a number of side chains of poly-epsilon-caprolactone (PCL). In this paper, we focus on the o/w emulsion stabilizing abilities of these novel PCL-DEX copolymers, using a recently developed optical analyzer (Turbiscan). The main advantage of Turbiscan is to detect the destabilization phenomena in non-diluted emulsion, much earlier than the naked eye's operator, especially in the case of an opaque and concentrated system. This study shows that PCL-DEX copolymers successfully stabilized ethyl acetate-in-water emulsions, even in the absence of additional surfactants, whereas they were not efficient in stabilizing methylene chloride-in-water emulsions which coalesced fast and irreversibly. The ethyl acetate-in-water emulsion stabilizing ability of PCL-DEX seemed to be related to the localization of their blocks with regard to the oil-water interface.
authors.affiliation: School of Pharmacy, Faculté de Pharmacie, Université Paris Sud, UMRCNRS 8612, tour D5, 1er étage, 5 rue JB Clément, 92926 Châtenay Malabry, France.
authors.forename: Caroline
authors.initials: C
authors.lastname: Lemarchand
authors.forename: Patrick
authors.initials: P
authors.lastname: Couvreur
authors.forename: Christine
authors.initials: C
authors.lastname: Vauthier
authors.forename: Dominique
authors.initials: D
authors.lastname: Costantini
authors.forename: Ruxandra
authors.initials: R
authors.lastname: Gref
mesh_terms: D000085:Acetates / Q000737:chemistry; D002208:Caproates / Q000737:chemistry; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D002712:Chlorides / Q000737:chemistry; D003911:Dextrans / Q000737:chemistry; D004355:Drug Stability; D004655:Emulsions / Q000737:chemistry*; D066298:In Vitro Techniques; D007783:Lactones / Q000737:chemistry; D008863:Microspheres; D009391:Nephelometry and Turbidimetry / Q000295:instrumentation / Q000379:methods; D009821:Oils; D011108:Polymers / Q000737:chemistry*; D013997:Time Factors; D019737:Transplants; D014867:Water
chemical_list: D000085:Acetates; D002208:Caproates; D002712:Chlorides; D003911:Dextrans; D004655:Emulsions; D007783:Lactones; D009821:Oils; D011108:Polymers; D014867:Water; C121056:caprolactone; C007650:ethyl acetate