Electrochemical behavior of flufenamic acid at amberlite XAD-4 resin and silver-doped titanium dioxide/ amberlite XAD-4 resin modified carbon electrodes

Abstract

Novel sensors based on carbon paste assorted with amberlite XAD-4 resin and silver-doped titanium dioxide/amberlite XAD-4 resin (Ag-TiO₂/XAD) were designed and employed for sensitive detection of flufenamic acid (FFA). The main objective of this study is to develop novel electrochemical sensors for more sensitive and selective detection of FFA and to propose its oxidation mechanism. In this perspective, we have developed modified electrodes using amberlite XAD-4 matrix and Ag-TiO₂/XAD-4 mixture. These sensors when used in conjunction with different voltammetric techniques to observe enhanced outcome on FFA electrode reaction in PBS of pH 7.0. Our data confirmed exceptional stability, sensitivity, and quick responses for FFA. The effect of modifier, analyte concentration, pH of buffer solution, pre-concentration time, and sweep rates on electrochemical behavior of FFA was investigated. The current intensities were linearly proportional to the concentration of FFA. From the calibration plot of different concentrations of FFA, the detection limit of 3.6 nM at XAD-CPE and 1.2 nM, respectively at AgTiO₂/XAD-CPE were obtained. The estimation of FFA in biological as well as clinical samples was achieved using the chemically modified electrodes.

Keywords: Amberlite XAD-4; Biological fluid analysis; Electrochemical behavior; Flufenamic acid; Silver-doped TiO(2).