Application of Poly Dl‐Phenylalanine Modified Carbon Nanotube Electrode for Sensitive and Selective Detection of Tinidazole

The present study aimed to design an electrochemical sensor for the detection of tinidazole (TN) by carbon nanotube electrode (CNTE) modified with dl‐phenylalanine (DL‐PA). The unmodified carbon nanotube electrode (UMCNTE) and poly (DL‐PA) modified carbon nanotube electrode (P(DL‐PA) MCNTE) were characterized by Scanning emission microscopy (SEM) images. Electrochemical techniques like cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and differential pulse voltammetry (DPV), were implemented to evaluate the efficiency of the developed electrode toward the detection of TN. The impact of pH on the modified electrode showed that the P(DL‐PA) MCNTE gave a good voltammetric response at pH 3.5. The effect of accumulation time, scan rate, and variation of concentration of TN at the surface of the developed sensor was analyzed. The scan rate study showed that the reduction reaction of TN involves a two‐electron transfer process and it is adsorption‐controlled. The detection limit studies for CV and DPV gave good linearity in the linear range 0.6 μM to 100.0 μM and 3.0 μM to 100.0 μM respectively. The limit of quantification (LOQ) and limit of detection (LOD) concerning CV were found to be 0.65 μM and 0.19 μM respectively. The LOQ and LOD for DPV were calculated to be 0.33 μM and 0.10 μM respectively. The P(DL‐PA) MCNTE showed good anti‐interferent properties. The developed sensor has good stability, repeatability, and reproducibility for the analysis of TN. The P(DL‐PA) MCNTE was successfully employed in the real sample analysis. The present study illustrates the determination of TN by using P (DL‐PA)MCNTE. The graphical depicts the preparation of P (DL‐PA)MCNTE, the first step involves the formation of carbon nanotube paste, the prepared paste was embedded on the cavity of the Teflon tube. Thus, UMCNTE is obtained, it was then modified by electropolymerization of DL‐PA on the UMCNTE so P (DL‐PA)MCNTE was obtained. The prepared electrode was then used for the voltametric analysis of TN and it was applicable on the pharmaceautical sample.