Design and Evaluation of Acyclovir Niosomes

The current study aims to formulate and evaluate acyclovir loaded niosomes for sustained release of acyclovir. Stable Acyclovir loaded Niosomes can be prepared by hand shaking method and ether injection method with Span 80 and cholesterol in the ratio of 1:1, 2:1, and 3:1. Preformulation studies and drug excipients compatibility studies was done initially and results directed the further course of formulation. Most of the vesicles are spherical in shape, the size range of the vesicles, fall in the narrow size range of 0.5-5 and 0.5-2.5 by hand shaking method and ether injection method respectively. A high % of Acyclovir can be encapsulated in the vesicles (75-84%) prepared by hand shaking method. Concentration of non-ionic surfactant such as Span 80 might influences the drug release pattern of all formulation. In vitro release of Acyclovir from niosomes was very slow when compared to the release from pure Acyclovir solution. Drug release studies showed that the niosomal preparation was stable at refrigeration temperature (40C). The vesicles prepared by hand shaking method were found to be larger in size as compared to vesicles prepared by ether injection method. Almost constant drug release was observed in all formulations indicating zero order release pattern.