New sensing material of molecularly imprinted polymer for the selective recognition of sulfamethoxazole in foods and plasma and employing the Taguchi optimization methodology to optimize the carbon paste electrode

Abstract

A new man-tailored biomimetic sensor for sulfamethoxazole host–guest interactions and potentiometric transduction is presented. The host cavity was shaped on a polymeric surface assembled with methacrylic acid monomers by radical polymerization. Molecularly imprinted particles (MIP) were mixed with graphite powder, paraffin oil and ionic site. Using the Taguchi method, this study analyzed the optimum conditions for preparing the carbon paste electrode. The controllable factors used in this study consisted the weights of (1) MIP, (2) paraffin oil, (3) graphite, and (4) the ionic site. The percentage contribution of each controllable factor was also determined. MIP-modified electrode exhibited a Nernstian response (57.2 mVdecade−1) in a wide concentration range of 6.0 × 10−8 to 3.1 × 10−3 mol L−1 with a lower detection limit of 3.5 × 10−9 mol L−1. The sensor was successfully applied to the determination of sulfamethoxazole concentrations in foods and plasma.