Silver nanostructure on ablated silicon wafer prepared via pulsed laser ablation for surface enhanced Raman spectroscopy

We propose and develop a simple and cost-effective method to fabricate surface enhanced Raman scattering (SERS) substrates for the trace detection of antibiotics. A nanostructured silicon (Si) surface is prepared by the pulsed laser ablation (PLA) of a Si wafer in distilled water. Silver nanoparticles (AgNPs) synthesized via PLA in distilled water are deposited on the ablated Si surface to form a SERS substrate (AgNP/aSi). Malachite green (MG) is used as a probe analyte to examine the SERS activity of the AgNP/aSi substrate. The AgNP/aSi substrate can yield an SERS spectrum of MG with high resolution at a minimum concentration of 0.01 ppm. Using the AgNP/aSi substrate, we investigate its capacity for detecting tetracycline (TC) residue in shrimp. The Raman peak intensities at 1320 cm(-1) for TC concentrations from 10 to 0.1 ppm show a linear relationship with the corresponding logarithmic concentrations. Our simple and efficient method can be used for the trace detection of MG, TC, and other antibiotics in various applications via SERS.