A Simple and Sensitive Poly-1,5-Diaminonaphthalene Modified Sensor for the Determination of Sulfamethoxazole in Biological Samples

Sulfamethoxazole (SMZ), an antibacterial sulfonamide drug, has been selectively determined using poly-1,5-diaminonaphthalene (p-DAN) modified glassy carbon electrode (GCE). The modified sensor was characterized by field emission scanning electron microscopy (FE-SEM), electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV). SMZ showed linear response in the concentration range of 0.5-150 mu M by using square wave voltammetry (SWV) and the detection limit was found to be 0.05 nM with sensitivity of 0.085 mu A mu M-1. The proposed sensor has been successfully employed to determine SMZ in the pharmaceutical tablets and human urine samples.