title: Quantitative effects of interacting variables on vitamin K1, phylloquinone, entrapment in liposomes.
abstract: Vitamin K1 is poorly absorbed by the oral route in certain diseased conditions. Entrapment of this vitamin in liposomes is expected to improve oral absorption. In this study, vitamin K1 has been encapsulated into multilamellar vesicles (MLVs) composed of either egg phosphatidylcholine (egg PC, EPC) or dipalmitoyllecithin (DPPC) by the classical film method involving hydration of lipids by either hand shaking or vigorous vortex mixing. Amounts of vitamin K1 ranging from 4.4 to 22.1 microMol were employed to medicate liposome suspensions (26 microMm or 13.6 microM). A 2(3) factorial design was employed to quantitative the effects of the interaction of certain variables viz: nature of lipid (L), method of agitation (M) and initial drug concentration (C), on encapsulation capacity (EC) of liposomes. The results of this study suggest, in particular, that the concentration of the drug (C) and the nature of the lipid-drug interactions (L-C) are the most influential variables. This probably infers that any pre-formulation studies with this drug delivery system should start with a consideration of L-C interaction. A negative correlation was found between initial drug concentration and encapsulation capacity of liposomes.
mesh_terms: D015060:1,2-Dipalmitoylphosphatidylcholine; D000933:Antifibrinolytic Agents / Q000008:administration & dosage / Q000737:chemistry; D004339:Drug Compounding; D016503:Drug Delivery Systems; D006801:Humans; D008081:Liposomes; D010713:Phosphatidylcholines; D010837:Vitamin K 1 / Q000008:administration & dosage / Q000737:chemistry
chemical_list: D000933:Antifibrinolytic Agents; D008081:Liposomes; D010713:Phosphatidylcholines; D015060:1,2-Dipalmitoylphosphatidylcholine; D010837:Vitamin K 1