Detection of Antibiotic-Contaminated Water by Laser-Induced Highly Sensitive Optical Fiber SERS Probes

Optical fiber surface-enhanced Raman spectroscopy (SERS) probes offer a rapid and highly sensitive approach of pharmaceuticals from environmental sources. SERS hot spots are recognized to occur when two noble nanoparticles are brought close enough to each other. However, controlling the gap size between nanoparticles on the fiber end faces at the nanoscale remains a great challenge without expensive and bulky instruments. Here, we report a precisely and simply regulated method that employs laser-controlled capture of Polyvinylpyrrolidone-shaped silver particles to generate silver clusters with nanoscale dimensions and gaps on the fiber end faces. The produced SERS probes can detect Rhodamine B solutions down to concentrations of 10(-14) M, exhibiting excellent detection sensitivity and well reproducibility. The outstanding performance of these fiber SERS probes enables label-free monitoring of low concentrations at 0.01 mu g/mL of antibiotics in deionized water, and 0.1 mu g/mL of antibiotics in tap water and river water without complex pretreatment processes. The laser-induced SERS probe boasts rapid response, highly specific recognition, and cost-effective operation in the realm of environmental monitoring, offering an innovative solution for the efficient screening of trace antibiotic contamination.