Synthesis of Cu4O3 Nanoparticles Using Pumpkin Seed Extract: Optimization, Antimicrobial, and Cytotoxicity Studies

This study explores a green synthesis method for copper oxide (Cu4O3) nanoparticles using pumpkin seed extract, which acts as both a reducing and stabilizing agent. The nanoparticles, sized between 8.92 and 55.84 nm, were characterized by various techniques and showed a maximum yield of 89.87% under optimized conditions. They exhibited significant antibacterial activity against Bacillus subtilis and moderate cytotoxic effects on lung and colon cancer cell lines. Computational studies revealed a moderate HOMO–LUMO energy gap, suggesting potential interactions with biological systems. These results highlight the potential biomedical applications of these eco-friendly nanoparticles.