Biocidal activities of nickel oxide nanoparticles modified by copper and manganese, synthesized by green process

Abstract

In recent years, the development of dual dopant‐based nanoparticles (NPs) has gained significant attention as they possess exceptional physico‐chemical and biomedical properties, making them potential candidates for antimicrobial and anticancer uses. In this research, we successfully synthesized nickel oxide (NiO) and copper, manganese‐doped NiO (CuMn:NiO) NPs using a green synthesis method. The synthesis process involved Trigonella foenum‐graecum (T.f.graecum) leaves extract as a nucleating agent. The synthesized nanoparticles were confirmed by various physico‐chemical studies. Based on X‐ray diffraction analysis, the median size was determined as 36 nm for NiO and 32 nm for CuMn:NiO NPs. The antibacterial study revealed that CuMn:NiO NPs exhibited a higher zone of inhibition in contrast to both Gram‐positive (Streptococcus pneumoniae, Bacillus subtilis, Bacillus megaterium) and Gram‐negative bacteria (Klebsiella pneumoniae, Escherichia coli, Vibrio cholerae) compared with NiO NPs and commercial amoxicillin. The antifungal studies conducted against Candida albicans demonstrated that CuMn:NiO NPs exhibited enhanced efficacy in comparison to NiO NPs. In vitro testing against human breast cancer cells (MCF‐7) demonstrated the anticancer potential of NiO and CuMn:NiO NPs, supported by IC50 concentrations of 11 and 9 μg/mL, respectively. The photoluminescence (PL) spectra of NiO and CuMn:NiO NPs exhibited a green emission at 508 and 518 nm, respectively, which indicated the generation of active free radicals by the NPs. These findings suggest that CuMn:NiO NPs hold promise in the healthcare industry.