Eco-friendly biosynthesis of copper oxide nanoparticles using black tea extract: multifaceted biological activities...

This study presents a cost-effective one-step biosynthesis of CuONPs using black tea extract as a reducing and capping agent, highlighting its eco-friendly potential for biomedical applications such as antioxidant, antimicrobial, anticancer, and drug delivery. The structural and optical properties of the synthesized CuO NPs were characterized through UV-Vis spectroscopy, XRD, FTIR, DLS, TEM, and FESEM. The CuONPs demonstrated significant biological activities, including 87.3% antioxidant activity at 1000 mg/L and 96.5% antidiabetic activity at 200 mg/L. Remarkably, they completely degraded supercoiled DNA at all tested concentrations and exhibited potent antimicrobial effects, particularly against P. aeruginosa and E. coli. The antibiofilm activities were also notable, with inhibition rates against S. aureus and P. aeruginosa ranging from 70% to 90%. Furthermore, the CuO NPs achieved 98.3% cell viability inhibition at a concentration of 15 mg/L. As potential anticancer agents, they displayed strong efficacy against human breast cancer (MCF-7) cells, significantly reducing cell proliferation after 48 hours of treatment at 5 μg/mL. CuONPs were evaluated as carriers for tamoxifen (TMX). Box-Behnken design optimized TMX adsorption based on pH, initial drug concentration, and NP amount. Release studies showed over 50% TMX release at pH 7.4 within 2 hours, stabilizing around 56% after 8 hours.