Encapsulation of nystatin in nanoliposomal formulation: characterization, stability study and antifungal activity against Candida albicans

Polyene antibiotics are a group of macrolide lactones that have antifungal activity against a wide variety of fungi. Administration of this group of antibiotics have recently increased due to the use of immunosuppressive drugs and increasing incidence of AIDS (1,2). Nystatin, the first polyene drug to be identified, is active against a wide variety of fungal pathogens including Candida, Aspergillus, Histoplasma and Coccidioides spp. (4,5,6). Nystatin has a similar structure to amphotericin B, but has a broader spectrum of action than amphotericin B and is used for the treatment of cutaneous, vaginal and oral candidiases by oral, pleural inhalation and topical administration (7-9). Nystatin, has a broad spectrum of activity, but due to its low solubility in injectable solvents and toxicity, its use in the treatment of systemic fungal infections is limited (7,8). Unfortunately its clinical use, other than by topical application, has been Abstract In this study, nystatin liposomal formulation was prepared and characterized. The physicochemical properties of formulations including vesicle size, drug entrapment stability and in vitro release were studied. The highest entrapment efficiency of nystatin into liposomes was obtained about 70% when cholesterol (CHO) was added to the formulations prepared with dipalmitoylphosphatidylcholine. In addition, the drug entrapment efficiency was decreased when distearoylphosphatidylcholine was used but it was improved by addition of CHO and hydration with 9% sucrose solution. Liposomes with uniform size distribution and average size of 100 nm were produced. Long term stability study indicated that the lyophilized liposomal nystatin was physically stable for at least 6 months at 4 C. In vitro anti-fungal activity of liposomal nystatin was found to be more effective than free nystatin against Candida albicans.