Development of G-Ag and C-Ag Nanoparticle-Based Biosensor for Benzoic Acid Detection

Abstract

In this study, an efficient electrochemical sensor for the highly sensitive detection of benzoic acid (BA) is developed using silver nanoparticles (Ag NPs) obtained by two different methods: the green synthesis method (G-Ag) and the chemical synthesis method (C-Ag). Linden flower extract is prepared and used for the biosynthesis of Ag NPs. Sodium borohydride, NaBH₄, is used as a reducing agent in chemical synthesis. Ag NPs are characterized by the X-ray diffraction (XRD) method, scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, and UV-visible spectrometry. According to the XRD results, the crystal sizes for G-Ag and C-Ag are calculated to be 24.07 and 5.91 nm, respectively. G-Ag and C-Ag NP-modified glassy carbon electrodes (GCEs) and cyclic voltammetry (CV) and differential pulse voltammetry (DPV) are used as electrochemical methods to determine BA. The limits of detection of G-Ag and C-Ag NP-modified GCEs are calculated as 1.67 mM limit of quantification and 10 mM, respectively. The linear ranges of GCEs modified with nanomaterials are determined as 2.40-8.01 mM for C-Ag and 4.84-14.66 mM for G-Ag. The study is significant in that the NPs obtained by the biological synthesis method showed as good activity as the particles synthesized by the chemical method.

Keywords: Ag nanoparticles; benzoic acid; chemical synthesis; electrochemical sensors; green synthesis.