A New Amphotericin B-loaded Trimethyl Chitosan Nanoparticles as a Drug Delivery System and Antifungal Activity on Candida albicans Biofilm

Document Type: Original Articles


1 1- Departmen of Microbiology, Medical and Veterinary Mycology, Faculty of Veterinary Specialized Science. Science and Research Branch, Islamic Azad University, Tehran, Iran

2 Department of Human Vaccine and Serum, Razi Vaccine and Serum Research Institute, Agricultural Research, Education and Extension Organization, Karaj, Iran

3 Department of Pathobiology, Faculty of Veterinary Specialized Science, Science and Research Branch, Islamic Azad University, Tehran, Iran.

4 Department of Tuberculosis, Razi Vaccine & Serum Research Institute, Agricultural Research, Education and Extension Organization, Karaj, Iran


Amphotericin B (AmB) is an effective antifungal agent. However, the application of AmB is associated with a number of drawbacks and side effects. Application of Nanoparticles (NPs) is known to allow more efficient drug delivery to the target tissues than the traditional methods. In this study, the trimethyl chitosan (TMC) was synthesized from low molecular weight chitosan. TMC was then used for the preparation of TMC-NPs by the ionic gelation method. Then AmB-loaded TMC-NPs (TMC-NPs/AmB) were prepared for and their potential application for drug delivery. The TMC-NPs and TMC-NPs/AmB were characterized for their structure, particle size, Zeta potential (ZP), polydispersity index (PDI), morphology, loading efficiency (LE), loading capacity (LC), in vitro release profile, release kinetic and entrapped AmB potency. Then the cytotoxicity and antifungal activity of TMC-NPs/AmB against Candida albicans biofilm were evaluated. In this study, quaternization percent of TMC estimated to be 36.4. The mean particle size of TMC-NPs and TMC NPs/AmB were 210±15 and 365±10 nm respectively, with a PDI of 0.30 and 0.4, ZP of +34±0.5 and +28±0.5 mV respectively. Electron microscopy analysis indicated uniform spherical shapes with smooth surfaces. The TMC-NPs/AmB indicated LE of 76% and LC of 74.04 % with a potency of 110%. The release profile of TMC-NPs/AmB was best explained by Higuchi model. The initial release after 10 h was 38% and the rate of release after 36 and 84 h was 67% and 76% respectively, which was significantly different (P<0.05) from previous time points. The minimum inhibitory concentration (MIC) 50% of NPs/AmB and AmB were 0.65 and 1.75 μg/mL and the MIC 80% were 1.95 and 7.75 μg/mL, respectively demonstrating a significant improvement in antifungal activity. The half-maximal inhibitory concentration for TMC-NPs/AmB and AmB were 86 and 105 μg/mL respectively, indicating a significant reduction in cytotoxicity and the adverse effect. This study could successfully introduce a practical method to synthesize a TMC-NPs. The encapsulation process was efficient and significantly improved the antifungal activity of AmB. The developed method can be applied to improve the routs of drug administration while reducing the adverse effects associated with traditional methods.