Formulation, characterization, and in vitro antifungal evaluation of liposomal terbinafine prepared by the ethanol injection method
نویسندگان
1 Student Research Committee, School of Medicine, Mazandaran University of Medical Sciences, Sari, Iran
2 Department of Biostatistics, Faculty of Health, Mazandaran University of Medical Sciences, Sari, Iran
3 Department of Medical Mycology, School of Medicine, Mazandaran University of Medical Sciences, Sari, Iran
4 Department of Infectious and Tropical Diseases, Research Center for Microbial Resistance and Communicable Diseases, Mazandaran
5 Department of Medical Parasitology, Ardabil University of Medical Sciences, Ardabil, Iran
6 Department of Medical Mycology, School of Medicine, Mazandaran University of Medical Sciences, Sari, Iran
7 Immunogenetics Research Center, Department of Medical Nanotechnology, School of Advanced Technologies in Medicine, Mazandaran University of Medical Sciences, Sari, Iran
8 Invasive Fungi Research Center, Communicable Diseases Institute, Mazandaran University of Medical Sciences, Sari, Iran
9 Department of Pathology, Mazandaran University of Medical Sciences, Sari, Iran
10 Department of Medical Mycology, School of Medicine, Mazandaran University of Medical Sciences, Sari, Iran
11 Department of Medical Mycology, School of Medicine, Mazandaran University of Medical Sciences, Sari, Iran
12 Cellular and Molecular Research Center, Mazandaran University of Medical Sciences, Sari, Iran
13 Invasive Fungi Research Center, Communicable Diseases Institute, Mazandaran University of Medical Sciences, Sari, Iran
14 Invasive Fungi Research Center, Communicable Diseases Institute, Mazandaran University of Medical Sciences, Sari, Iran
15 Department of Molecular Microbiology & Immunology, South Texas Center for Emerging Infectious Diseases, The University of Texas at San Antonio, San Antonio, Texas, USA
16 Student Research Committee, Faculty of Medicine, Mazandaran University of Medical Sciences, Sari, Iran
doi
10.22034/cmm.2025.345444.1686چکیده
Background and Purpose: Fungal infections necessitate advanced delivery systems to improve antifungal therapy. Terbinafine, a potent allylamine antifungal, faces clinical limitations due to poor solubility, low bioavailability, and toxicity. Liposomal encapsulation addresses these challenges by enhancing solubility, enabling controlled release, and reducing toxicity. In this study, a scalable ethanol injection method was used to develop terbinafine-loaded liposomes with optimized physicochemical properties. This study aimed to focus on central nervous system-targeted delivery to combat resistant fungal infections while minimizing systemic toxicityMaterials and Methods: Twenty liposomal formulations were prepared using phospholipids (e.g., dipalmitoylphosphatidylcholine [DPPC], hydrogenated soybean phosphatidylcholine) and characterized for size, zeta potential, polydispersity index, and morphology via dynamic light scattering and transmission electron microscopy. Encapsulation efficiency, drug release kinetics, colloidal stability (3 months), and cytotoxicity (human foreskin fibroblast 2 cells, 48-hour exposure) were evaluated. The M38-A2 method of the Clinical and Laboratory Standards Institute was used to calculate minimum inhibitory concentrations (MICs) of 16 azole-susceptible and -resistant Aspergillus fumigatus and Aspergillus flavus.Results: Liposomes exhibited sizes of 72–174 nm, zeta potentials between +2 and −15 mV, and a low polydispersity index (<0.3). Moreover, F12 (DPPC-based) demonstrated superior cumulative release, compared to F20, and attributed to the fluid bilayer of DPPC. Both formulations retained stability during storage. Cytotoxicity assays revealed minimal toxicity for free terbinafine (14.73% at 25 mg/mL) and significantly reduced toxicity for liposomal forms (6.77% for F12, p<0.05). The DPPC-based formulation achieved an encapsulation efficiency of 73.48%, ensuring a high drug payload and biocompatibility. The DPPC-based formulation achieved an encapsulation efficiency of 73.48%, ensuring a high drug payload and biocompatibility. Liposomal terbinafine and voriconazole exhibited good in vitro activity against both triazole-susceptible and -resistant Aspergillus isolates (MIC50=0.5 µg/mL).Conclusion: Based on the results, F12, with its sub-100 nm size, sustained release, and reduced cytotoxicity, emerged as a promising candidate for brain-targeted antifungal therapy. Its stability and high encapsulation efficiency support further evaluation in fungal isolates and in vivo models to optimize central nervous system biodistribution and therapeutic efficacy. In addition, this study underscored the promising in vitro activities of terbinafine and liposomal terbinafine against both triazole-resistant/susceptible A. fumigatus and A. flavus.
