Design and Synthesis of Liposomal Vancomycin and Evaluation of its Antibacterial Effects on Methicillin-Resistant Staphylococcus aureus

Liposomes, as nanocarriers, have developed advanced systems for transporting biological molecules, such as vaccine adjuvants, anti-cancer drugs, antifungals, and painkillers. In this study, liposomal vancomycin was prepared and its antimicrobial effect on methicillin-resistant Staphylococcus aureus (MRSA), as one of the most important nosocomial infections, was investigated.

Liposomes were prepared using hydration and dehydration methods. Their surface morphology was measured using a scanning electron microscope (SEM), medium size of DLS (Dynamic Light Scattering), zeta potential, liposome stability, and drug loading rate. Antimicrobial effects and minimum inhibitory concentration (MIC) were performed using disc diffusion and microdilution methods, respectively, and the results were compared with the original form of the drug.

Liposomal vancomycin was performed in several syntheses with DSPC:DCP: Cholesterol ratio, which showed the best result with a ratio of 7:2:1. Its size was reported with 154 nm in DLS and 100 nm in SEM. The drug loading rate was 61.6% and liposome stability was 30 days. The mean diameter of non-growth halos in the samples was 19.44 mm in free form and 22.7 mm in liposomal form. The MIC of free form was 1.2 mg/ml and liposomal form was 4.27 mg/ml.

The results indicated that the liposomal vancomycin form was stable for up to 30 days and its antimicrobial effects showed better results than the free vancomycin form against the MRSAs isolated from the hospital.