Characteristics of tin oxide nanoparticles produced by pulsed laser ablation technique in various concentrations of chitosan liquid and their potential application as an antibacterial agent

Tin oxide nanoparticles (SnO2 NPs) have become a potential candidate as an antibacterial agent for gram-negative and gram-positive bacteria. In this present work, SnO2 NPs have been successfully synthesized in the chitosan liquid medium by using the pulse laser ablation method utilizing quite low energy Nd:YAG laser (30 mJ). The produced tin oxide nanoparticles were then applied as an antibacterial agent for gram-negative and gram-positive bacteria. Experimentally, a pulse Nd:YAG laser beam is irradiated and focused on the surface of a high-purity tin metal plate placed at the bottom of the Petri dish that is filled with chitosan liquid medium. The effect of chitosan concentrations (0.05%, 0.1%, and 0.2%) on the characteristics of produced SnO2 NPs was examined. The higher concentration of chitosan (0.2%) gains the smallest diameter size (15.05 nm) and lowest concentrations of produced tin oxide nanoparticles. The application of produced SnO2 NPs as the antibacterial agent was demonstrated using gram-negative (Escherichia coli) and gram-positive (Bacillus subtilis) utilizing disk diffusion technique. The result certified that increment of the SnO2 NPs concentrations (100, 125, and 150 ppm) increases the diameter of inhibition zone (DIZ) both for E coli and B subtilis bacteria, which approve that the produced tin oxide nanoparticles can effectively be used as antibacterial agents for both gram-negative and gram-positive bacteria.