Antibacterial and antibiofilm activities of amikacin-conjugated gold Nanoparticles: A promising formulation for contact lens preservation

Contact lenses are a widely utilized tool for both cosmetic and eyesight corrective purposes. Additionally, they are a direct contributor to microbial keratitis and corneal infections, particularly those caused by Pseudomonas aeruginosa infections. This study aimed to conjugate amikacin to gold nanoparticles (GNPs) and assess the formulation's antibacterial and antibiofilm formation within contact lenses. The safe and environmentally friendly method, Pulsed laser ablation (PLAL), was used to prepare the amikacin-conjugated gold nanoparticles (Am@GNPs). The characterization of the produced formula was studied using a spectrophotometer UV light, transmission electron microscopy (TEM), X-ray diffraction (XRD), and Fourier transforms infrared (FT-IR). Compared to the GNPs and the antibiotic amikacin, the anti-biofilm activity of Am@GNPs was measured using atomic force microscopy (AFM), whereas the antibacterial activity was measured by the well diffusion and microdilution methods against the most prevalent contact lens microbial isolates, i.e., P. aeruginosa and Streptococcus pneumonia. The formulation, Am@GNPs, was induced higher inhibition zone and lower MIC values compared to the GNPs and the amikacin antibiotic, the effect which was more pronounced against P. aeruginosa than S. pneumonia bacterial strains. Application of Am@GNPs to the contact lenses also potentially reduced P. aeruginosa and S. pneumoniae biofilm formation, with the lowest biofilm thickness compared to the amikacin and GNPs, as demonstrated by the AFM scanning. According to current findings, the prepared Am@GNPs exhibited substantial antibacterial effects and could be a potential preservative formula for contact lenses and other eye-related medical devices.