title: Vitamin E nanoemulsions characterization and analysis.
abstract: The aims of this work were to characterize vitamin E/canola oil nanoemulsions and to develop a practical RP-HPLC method for vitamin E acetate estimation in the canola oil nanoemulsions. Currently available methods to analyze vitamin E in lipid-emulsions are time-consuming and do not allow adequate separation of vitamin E and its esters. The nanoemulsions were characterized for partition coefficient between emulsion phases, drug loading, free drug, micellar solubilization, encapsulation efficiency and vitamin E concentration in the emulsion external aqueous phase as a function of time. Formulation stability under stress conditions was also evaluated. The nanoemulsions were stable during the test period at 25 and 32 °C with no significant change in mean droplet diameter. The results suggest that prolonged release of lipophilic drugs can be achieved using nanoemulsions. The RP-HPLC method developed showed linearity, selectivity and efficiency. To the best of our knowledge, this is the first practical method for vitamin E analysis in lipid-emulsions. This method may also be applied to the analysis of vitamin E and its esters in other lipid formulations, and for quality control purposes.
authors.affiliation: Department of Pharmaceutical Sciences, School of Pharmacy, University of Connecticut, Storrs, Connecticut, 06269, United States.
authors.forename: Jacqueline M
authors.initials: JM
authors.lastname: Morais Diane
authors.affiliation: Department of Pharmaceutical Sciences, School of Pharmacy, University of Connecticut, Storrs, Connecticut, 06269, United States. Electronic address: d.burgess@uconn.edu.
authors.forename: J
authors.initials: J
authors.lastname: Burgess
mesh_terms: D002626:Chemistry, Pharmaceutical; D002851:Chromatography, High Pressure Liquid; D056148:Chromatography, Reverse-Phase; D003692:Delayed-Action Preparations; D004337:Drug Carriers; D004655:Emulsions; D005229:Fatty Acids, Monounsaturated / Q000737:chemistry*; D007700:Kinetics; D016014:Linear Models; D008823:Micelles; D053758:Nanoparticles; D036103:Nanotechnology; D000074262:Rapeseed Oil; D012995:Solubility; D013678:Technology, Pharmaceutical / Q000379:methods; D024502:alpha-Tocopherol / Q000737:chemistry*
chemical_list: D003692:Delayed-Action Preparations; D004337:Drug Carriers; D004655:Emulsions; D005229:Fatty Acids, Monounsaturated; D008823:Micelles; D000074262:Rapeseed Oil; D024502:alpha-Tocopherol
keywords: RP-HPLC analytical method for vitamin E; Vitamin E acetate; Vitamin E/canola oil nanoemulsions