Fabrication and optimization of amoxicillin-loaded niosomes: an appropriate strategy to increase antimicrobial and anti-biofilm effects against multidrug-resistant strains.

In this study, different formulations of amoxicillin-loaded niosomes were fabricated using the thin-film hydration method and their physicochemical properties were determined using scanning electron microscopy (SEM), dynamic light scattering (DLS), and Fourier-transform infrared (FTIR) spectroscopy. The optimum prepared niosomes had a spherical morphology with an average size of 170.6 ± 6.8 nm and encapsulation efficiency of 65.78 ± 1.45%. The drug release study showed that the release rate of amoxicillin from niosome containing amoxicillin was slow and 47 ± 1% of the drug was released within 8 h, while 97 ± 0.5% of the free drug was released. In addition, amoxicillin-loaded niosome increased the antimicrobial activity by 2-4 folds against multidrug-resistant (MDR) strains using broth microdilution assay. Moreover, at 1/2 minimum inhibitory concentrations, amoxicillin-loaded niosome significantly enhanced the anti-biofilm activity compared to free amoxicillin. Amoxicillin-loaded niosome had negligible cytotoxicity against HEK-293 normal cell line compared to free amoxicillin. The free niosomes exhibited no toxicity against HEK-293 cells and presented a biocompatible nanoscale delivery system. Based on the results, it can be concluded that amoxicillin-loaded niosome can be used as a promising candidate for enhancing antimicrobial and anti-biofilm effects against MDR strains of .