Green Synthesis and Biomedical Potential of L-Ascorbic Acid-Stabilized Copper Sulfide Nanoparticles as Antibacterial and Antioxidant Agents.

Abstract

Background: Copper sulfide nanoparticles (CuS NPs) are promising materials for a variety of biomedical applications, particularly as antimicrobial and antioxidant agents. The main objective of this study was to synthesize CuS NPs and evaluate their efficiency as an antioxidant and antibacterial agent.

Methods: CuS NPs were prepared in a single step process using L-ascorbic acid as the stabilizing agent. Systematic structural and morphological characterization was performed using standard techniques of X-ray diffraction (XRD), Fourier-transform infrared (FT-IR) spectroscopy, and scanning (SEM) and transmission electron microscopy (TEM). Further, agar well disk-diffusion method was applied for determination of the antibacterial sensitivity and minimum inhibitory concentration (MIC) against multiple pathogenic bacterial strains. The antioxidant potential was evaluated by performing total reduction capability, and nitric oxide (NO) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging activities at multiple doses, with L-ascorbate as the reference.

Results: The results indicated amorphous nature of the CuS NPs with the size range of 8.17 to 9.63 nm. FI-IR confirmed presence of several bioactive functional groups required for the reduction of copper ions. Additionally, our CuS NPs showed robust antibacterial activities against bacterial species such as Escherichia coli and Staphylococcus aureus) in the agar well diffusion assays, with zone of inhibition values ranging between 21 and 23 mm. CuS NPs also showed potent dose-dependent antioxidant activity.

Conclusion: CuS NPs prepared in this study in a cost- and time-efficient manner have excellent antibacterial and antioxidant properties with the potential to be applied for different biomedical applications.