Abstract
Numerous studies have shown that a variety of pharmaceuticals such as quinolones have been detected in the vicinity of municipal wastewater discharges and livestock agricultural facilities. Many of those works have been employed conventional analytical techniques and traditional methods of detection. However, in many cases these detection methodologies are time consuming and generate waste, which can be overcome using Surface-enhanced Raman spectroscopy (SERS) as analytical technique. In the present work, silver nanoparticles (AgNP) films were prepared on amine-modified glass slides with different number of depositions. The AgNP aggregates films were tested as SERS substrates using 4-aminobenzenethiol (4-ABT) as model Raman molecule. A trend between the 4-ABT SERS response and the number of AgNP deposition could be identified, which can be associated with the formation of AgNP aggregates. The aggregation effect could be quantified by calculating the enhancement factor (EF), which was on order of 106 for the film with fiveAgNP depositions. This optimized AgNP film was employed as SERS sensor of Levofloxacin in different concentrations, which was easily detected from 10-4, 10-5, and 10-6 mol L-1 solution. Also, the SERS spectral profile are rich in information, which allowed to describe the chemical interaction between the Levofloxacin molecules and the AgNP sensor surface. This study provides an efficient method for detecting of Levofloxacinusing AgNP SERS sensor, which can be extended for others quinolones.
