Pulsed Laser-Ablated CuO Nanoparticles and Femtosecond Laser Irradiation in Targeting Common Ocular Pathogens

Abstract

Introduction: Nanotechnology holds promise for advancing antibacterial therapies, particularly through the utilization of metal oxide nanoparticles and innovative treatment strategies.

Objectives: This study explores the synthesis and antibacterial properties of copper oxide nanoparticles (CuO NPs) produced via Pulsed Laser Ablation in Liquids (PLAL) and their potential application in ocular infection treatments.

Methods: CuO NPs were synthesized by irradiating a copper sample with a 532 nm nanosecond laser at varying powers (500-900 mW) for 30 minutes. The nanoparticles were characterized for their optical absorption, average size, and concentration. The antibacterial effectiveness of these nanoparticles was evaluated against both Gram-positive bacteria (Staphylococcus aureus) and Gram-negative bacteria (Pseudomonas aeruginosa). The study also evaluated the biocompatibility of CuO NPs with retinal epithelial cells (ARPE-19) using the MTT assay.

Results: Transmission electron microscopy (TEM) confirmed the production of CuO NPs with dimensions ranging from 4.6 to 6.5 nm. Results indicated that CuO NPs exhibit a concentration-dependent antibacterial activity which is enhanced when combined with femtosecond laser irradiation at 400 nm. Despite these antibacterial effects, the cytotoxicity of CuO NPs remains a concern, highlighting the need for further research to optimize their safety and effectiveness for clinical applications.

Conclusions: Optimal laser settings produced nanoparticles within the quantum dot size range, with the highest yields achieved at 900 mW power. While the antibacterial efficacy of CuO NPs shows especially when combined with femtosecond laser treatment, further studies are necessary to address safety concerns and refine production techniques for clinical viability.