Exploring The Potential of Copper Nanoparticles Against Gram-Positive and Gram-Negative Pathogenic Bacteria

Copper nanoparticles (CuNPs) are in urgent demand in the multi-drug-resistant bacteria (MDR) matter. In this context, this study sought to synthesize eco-friendly copper nanoparticles (CuNPs) and estimate their anti-bacterial ability against gram-positive and gram-negative multi-drug resistance bacteria to antibiotics. CuNPs were synthesized using an aqueous solution of copper sulfate CuSO4 (100mM) with an aqueous leaf extract (3%) with a volume ratio of 1:1. The characterization of CuNPs was performed via an ultraviolet-visible spectrophotometer (UV-vis), zetasizer, zeta potential, scanning electron microscopy (SEM) and Fourier-transform infrared spectroscopy (FTIR). The antibacterial potential of CuNPs against Gram-positive (S. haemolyticus, S. pneumonia) and Gram-negative (K. pneumonia and P. mirabilis) pathogenic bacteria, was evaluated. The change of the mixture colour from light green to brown confirms CuNP synthesis. CuNPs demonstrated a Surface Plasmon Resonance (SPR) peak at 570 nm, with a size of 78.82 (d.nm) and 75-85 nm using zetasizer and SEM, respectively, with a semi-spherical shape. Zeta potential showed a value of -20.7mV and FTIR analysis revealed the biochemical compounds of plant extract. CuNPs illustrated remarkable antibacterial effectiveness with entire hemocompatibility with red blood cells. The antibacterial activity of CuNPs (200 µg/ml) showed inhibition zones of 20.00±1.00 mm, 17.66±0.66 mm, and 16.66±0.66 mm against K. pneumonia, P. mirabilis, and S. haemolyticus, respectively. Further, for the CuNPs at 50 and 100 µg/ml, the inhibition zones for P. mirabilis bacteria were 15.5±0.50 mm and 18.00±1.00 mm, respectively. Thus, CuNPs could be promisingly exploited to deter pathogenic bacteria with no recorded toxicity to human RBCs.