Preparation and antifungal activity of spray-dried amphotericin B-loaded nanospheres

Background and the purpose of the study: Amphotericin B (AmB) which is an appropriate antibiotic for the treatment of mycosis has many toxic effects including nephrotoxicity. Recently preparation of a new drug loaded nanoparticles for the reduction of toxicity and increase in the effectiveness of AmB has been reported. The objective of this study was to prepare and evaluate in vitro and in vivo efficacy of the spray-dried AmB-loaded nanospheres. AmB-loaded nanospheres was prepared by means of nanoprecipitation method. The spray-dried nanospheres was prepared by using aerosil and AmB entrapment efficacy was measured by HPLC method. Minimum inhibitory concentration (MIC) of AmB-loaded nanospheres against Candida albicans (ATCC 90028) was determined by using microdilution method and its in vitro haemolytic effect and antifungal efficacy on infected rabbits was also analyzed. The entrapment efficacy for AmB loaded nanospheres was 65.2% ± 3. The MIC of AmB-loaded nanospheres against C. albicans compared to the free antibiotic was lower significantly. Also, the AmB-loaded nanospheres found to be 9.5 times less toxic than free AmB on human red blood cells. In vivo testing indicated that AmB-loaded nanospheres have a stronger protective effect against candidiasis compared to the free AmB. Results of this study suggest that prepared spray-dried AmB-loaded nanospheres would be a good choice for the treatment of mycosis because of low toxicity and high stability and effectiveness.