Abstract
The motive of this work is to study the molecular interaction between valeric acid (VA) molecules as analyte and silver nanoparticles as substrates. Therefore, a new approach was established for an efficient detection of VA using the surface enhanced Raman scattering (SERS) technique. Silver nanoparticles (Ag-NPs) were synthesized by the reduction procedure and used as a SERS substrate for the detection of VA. The structure and morphology of the silver nanoparticles were characterized by Raman spectroscopy, UV spectroscopy, and transmission electron microscopy. The UV-visible spectra showed a maximum absorption of around 420 nm for the synthesized Ag-NPs. TEM image showed the spherical structure of the Ag-NPs. Possible modes of VA-Ag-NP interactions resulting in SERS enhancement were investigated via density functional theory (DFT) calculations. The most enhanced SERS band was utilized for a trace identification of VA in aqueous media. A calibration curve was established with a wide dynamic range, and a detection limit of 10 x 10(-)(10) M of VA was successfully achieved. The results support further enhancement in the applications of SERS in trace level detection of different targets. (C) 2018 Elsevier B.V. All rights reserved.