An efficient and well-organized sensing process of SERS sensors via synthesis of nanoparticles with laser pulse repetition rate

This work concerns improving the sensing process of Bisphenol A in drinking water using Ag core/Au shell nanoparticles (AgAu-C/S NPs) prepared by various Laser Pulse Repetition Rate (LPRR) to synthesize an efficient and well-organized SERS sensor. The novel SERS substrate enhancing (AgAu-C/S NPs) was specifically designed to enhance the sensitivity and selectivity of bisphenol A (BPA) detection in drinking water. The (AgAu-C/S NPs) developments address fundamental gaps in the current research, particularly regarding improved detection limits and practical applications in real-world conditions. A precisely controlled pulsed laser ablation (LA) process was employed to synthesize Ag core/Au shell nanoparticles by targeting gold and silver with varying laser pulse repetition rates (LPRR) ranging from 300 to 600 pulses. This method enabled the production of nanoparticles with diverse sizes, colloidal densities, and variations in hot spot junction vacancies. The results exposed a significant dependence of the LIMIT of detection (LOD) and intensity enhancement factor (EF) on the LPRR. The lowest (LO D) and highest value in (EF) of 1 × 10^–10 M, and 140,000, respectively, were achieved at a LPRR of 500 pulses when compared with other rates. Owing to the high density, small size of the (AgAu-C/S NPs), and the presence of hot spot junctions, combined with their high specific surface area, the system demonstrates exceptional detection. This enables the efficient detection of bisphenol A (BPA) at concentrations as low as 2.6 × 10⁻⁶ M, which is below the globally accepted minimum intake limit.