Bio-fabrication of multifunctional CuO-ZnO nanocomposites for improved biomedical and industrial wastewater purification by experimental and molecular docking computational investigation

Abstract

The current research focused on the fabrication of copper oxide‑zinc oxide nanocomposites (CuO-ZnO NCs) using Ceropegia debilis plant extract. The green fabricated material was characterized to analyse its structural, optical, and morphological properties. The NCs showed maximum absorbance at 372 nm with an energy gap of 2.95 eV. XRD and XPS analysis confirms the existence of Cu and Zn in the fabricated CuO-ZnO NCs. The peak indexed at 36.2^⸰ revealed the crystalline nature of NCs. The SEM and TEM studies revealed the spherical morphology with an average size of 36.2 nm and 31.1 nm, respectively. Zeta potential analysis confirms the stability of CuO-ZnO NCs with a negative potential of −21.3. CuO-ZnO NCs exhibit good antimicrobial properties against Staphylococcus aureus and Trichoderma viride. Moreover, NCs showed remarkable induced apoptosis against A549 and MCF-7 with an IC₅₀ 27.25 μg/mL and 24.35 μg/mL, respectively. A molecular docking computational study was used to validate the experimental antibacterial efficiency of both plant extract and NCs. The protein, dihydropteroate synthase showed the highest binding efficiency of −7.27 Kcal/mol and -5.90 Kcal/mol for bioactive molecule and CuO-ZnO NCs, respectively. Furthermore, photocatalytic efficiency was examined through the breakdown of the toxic pollutant methylene blue under sunlight irradiation, the degradation efficiency to be 96.1 % after 90 min of irradiation. The results revealed excellent photocatalytic properties of CuO-ZnO NCs due to improved charge separation and reduced recombination rates. Hence, the present study suggests that the synthesized CuO-ZnO NCs through the green route hold promise for environmental remediation and biological applications.