Design and Antifungal Activity of Fluconazole and Nystatin Loaded Onto Silica Mesoporous

The emerging resistance of fungal species and the limited number of available antifungals have resulted in many efforts to design novel agents for the management of fungal infections. In the current research, fluconazole (FLU) and nystatin (NYS) were loaded onto the mesoporous material of MCM-41-NH-pydc as a new drug delivery system in order to study their antifungal activities. Fourier transform infrared spectroscopy (FTIR), x-ray diffraction (XRD), and energy-dispersive x-ray spectrometry (EDX) analyses were applied to identify MCM-41-NH-pydc before and after immobilization of FLU and NYS. Moreover, the release of FLU and NYS from MCM-41-NH-pydc was measured by high-performance liquid chromatography (HPLC). The antifungal activity of NYS/FLU-loaded mesoporous material was determined against standard/azole-resistant Candida species using the broth microdilution method according to Clinical & Laboratory Standards Institute (CLSI) guidelines. The encapsulation efficiency for FLU@MCM-41-NH-pydc and NYS@MCM-41-NH-pydc were obtained as 1000 and 250_mg/g respectively. The XRD results indicated that the crystal phase of the mesoporous material was preserved after immobilization of FLU and NYS. The FTIR spectra of FLU@MCM-41-NH-pydc and NYS@MCM-41-NH-pydc revealed successful loading. Moreover, EDX analysis confirmed the structure of FLU@MCM-41-NH-pydc. According to the results, loading the FLU onto the mesoporous material has resulted in a significant increase in the geometric mean for minimum inhibitory concentration (GM MIC), whereas no statistically significant difference was found between the GM MIC values of NYS and NYS@MCM-41-NH-pydc. The release of both loaded antifungal drugs in a pH-dependent manner and the sustained release of NYS from the mesoporous material are considerable advantages of these newly designed formulations.