GREEN SYNTHESIZED COPPER OXIDE NANOPARTICLES INCORPORATED WITH STARCH POLYVINYL ALCOHOL ELECTROSPUN NANOSCAFFOLDS EXHIBIT ENHANCED ANTIMICROBIAL ACTIVITY

Abstract

This study investigates the green synthesis, characterization, and antimicrobial efficacy of Ectocarpales algal extract mediated copper oxide nanoparticles (CuO NPs) loaded starch/PVA electrospun nanoscaffolds. UV-Visible spectroscopy confirmed the distinct optical properties of the algal extract (absorption peak at 300 nm, indicating π-π* transitions) and CuO NPs (sharp peak at 200 nm, signifying surface plasmon resonance). Fourier-transform infrared spectroscopy (FT IR) analysis revealed characteristic functional groups, including Cu–O bonds (860 cm⁻¹) in CuO NPs and polymer-related vibrations (1652 cm⁻¹, C=O stretching) in nanoscaffolds. X-ray diffraction (XRD) confirmed the monoclinic tenorite phase of CuO NPs (25 diffraction peaks) and semi-crystalline nature of nanoscaffolds (14 peaks). Scanning electron microscopy (SEM) imaging showed spherical CuO NPs and porous, fibrous nanoscaffolds with embedded NPs. Thermogravimetric analysis (TGA) indicated thermal stability, with nanoscaffolds exhibiting 31.1% weight loss up to 400°C. Zeta potential analysis demonstrated moderate colloidal stability (+14.03 mV). Antimicrobial assays revealed superior efficacy of nanoscaffolds against bacterial (E. coli, S. aureus) and fungal (A. niger, Penicillium spp.) pathogens compared to algal extract and CuO NPs alone. These findings highlight the potential of biosynthesized CuO NP-integrated nanoscaffolds for biomedical applications due to their structural integrity, thermal resilience, and enhanced antimicrobial performance.