EXPERIMENTAL INVESTIGATION OF ADVANCED SURFACE-ENHANCED RAMAN SPECTROSCOPY (SERS) FOR ULTRA-TRACE DETECTION AND MOLECULAR CHARACTERIZATION OF PHARMACEUTICAL CONTAMINANTS IN AQUATIC ENVIRONMENTS

Abstract

Pharmaceutical contaminants in aquatic environments pose significant environmental and public health risks, necessitating ultra-trace detection methods for effective monitoring. This study explores the application of surface-enhanced Raman spectroscopy (SERS) for the sensitive and selective detection of pharmaceutical pollutants, including ciprofloxacin, ibuprofen, and estradiol, in water samples. Utilizing silver (AgNPs) and gold (AuNPs) nanoparticle-based substrates, SERS achieved limit of detection (LOD) values as low as 0.5 ng/L, outperforming conventional techniques such as high-performance liquid chromatography (HPLC), liquid chromatography-mass spectrometry (LC-MS) and standard Raman spectroscopy. The enhancement factor and molecular interactions were analyzed, highlighting nanoparticle functionalization as a key contributor to signal amplification. Additionally, comparative performance assessments revealed that SERS offers a cost-effective, rapid, and field-deployable alternative to traditional analytical methods. However, challenges such as nanoparticle aggregation, matrix interferences, and substrate reproducibility remain critical limitations. Future research should focus on machine learningassisted spectral analysis, bio-inspired hybrid SERS substrates and large-scale validation for real-world applications in water quality monitoring and environmental remediation. The findings underscore SERS as a promising tool for pharmaceutical contaminant detection, offering high sensitivity, specificity and practical feasibility for environmental surveillance.