Nanotechnology in drug delivery is a rapidly expanding field. Nanosized liposomal preparations are already in use for efficient drug delivery with better therapeutic indices. Existing methods of liposome preparation are limited by problems of scale-up, difficulty in controlling size, and intercalation efficiency. Here we prepare amphotericin B-intercalated liposomes by a novel process where amphotericin B and purified phosphatidyl choline are solubilized in suitable solvent and precipitated in supercritical fluid carbon dioxide (known as a gas antisolvent technique), to obtain microsized particles that are subsequently introduced into a buffer solution. The morphology of liposomes was characterized through a phase-contrast microscope, and the particle size distribution studied by laser technique showed nanosize with a narrow range of size distribution (between 0.5 and 15 microm) and a higher intercalation efficiency. In vitro studies conducted using Aspergillus fumigatus (MTCC 870) strain proved to be efficient in the retardation of the growth of the organism.