Adriamycin-loaded niosomes: drug entrapment, stability and release.

The effect of encapsulation of adriamycin into niosomes, and its resultant chemical purity, was studied by means of HPLC and high-speed scanning spectrophotometry (the simultaneous use of which allowed investigation of potential non-fluorescent drug degradation products), and the process shown not to adversely affect the drug. Efficiency of entrapment of aqueous solutions of the drug was apparently dependent on neither vesicle composition nor method of production, and evidence of a degree of surfactant-adriamycin association was provided by the high entrapment values. Light-induced drug degradation was reduced by niosome encapsulation, and efflux of entrapped adriamycin was decreased by inclusion of cholesterol into the vesicles, in a manner similar to that reported for liposome preparations. Thus only chemically pure adriamycin was entrapped in, and released from, niosomes.