Application of synthetic alkyl glycoside vesicles as drug carriers. I. Preparation and physical properties.

Abstract

Alkyl glycosides formed lamellar vesicles like phosphatidylcholine vesicles (liposomes), and the application of these vesicles as drug carriers was attempted. Various alkyl glycosides were synthesized and vesicles were prepared with these glycosides. The encapsulation capacity of the vesicles was examined in relation to alkyl chain length, sugar moiety and lipid composition. The glucosides of myristyl, cetyl and stearyl alcohols formed vesicles, but those of lauryl, decyl and octyl alcohols did not. The vesicles of glucoside, galactoside and mannoside showed fairly good encapsulation capacity but those of lactoside showed low capacity. An appropriate ratio of glycoside, cholesterol and dicetylphosphate is an important factor for the formation of these vesicles, especially with regard to dicetylphosphate. The alkyl glycoside vesicles show longer lives on stage in an ampule at 20.degree. C than phosphatidylcholine vesicles. The stability in plasma was also examined. The glycoside vesicles showed rapid release of about 40% of the aqueous contents, but after that, they showed outstanding stability for 48 h in plasma at 37.degree. C. Phosphatidylcholine vesicles showed rapid release of only about 30%, but they disintegrated gradually and showed low encapsulation capacity (about 20%) after 48 h. The application of alkyl glycoside vesicles as drug carriers may be feasible.