Electrochemical sensing of brucine using polymer modified nanotube sensor

In this innovative approach, a methodology was formulated to simplify the electrochemical analysis of the specified anti-inflammatory and analgesic drug, brucine (BCN), in 0.2 M phosphate buffer solution (PBS) by preparing an affordable, easy to use, and eco-friendly carbon nanotube paste electrode (CNTPE). This method was created using an electrode treated with glutamic acid (GL) through electrochemical polymerization along with a bare carbon nanotube paste electrode (BCNTPE) using pH 7 for different cycles (5, 10, 15, 20), with ten cycles revealing the optimum peak. This study presents an innovative electrochemical sensor employing a polymerized glutamic acid (GL) modified carbon nanotube paste electrode (P-GL(MCNTPE)). The sensor is specifically designed to detect BCN with high sensitivity and selectivity. The prepared electrodes, namely P-GL(MCNTPE) and BCNTPE, are utilized for comprehensive material and system characterization using various electrochemical techniques, including cyclic voltammetry (CV), differential pulse voltammetry (DPV), scanning electron microscopy (SEM), and electrochemical impedance spectroscopy (EIS). The developed sensor noticeably enhanced the electrochemical activity of BCN when placed in a pH of 4.0 PBS (0.2 M). BCN undergoes a distinctive two-proton and two-electron transfer process. Scan rate studies reveal that the electrode surface behaviour is largely governed by diffusion control. By varying the BCN concentration at pH of 4.0 in a scan rate of 0.1 V/s using DPV technique, the lower limit of detection was found to be 1.5 × 10^–8 M, and the lower limit of quantification was determined to be 5 × 10^–8 M. These measurements were obtained as the BCN concentration varied from 0.2 to 1.2 µM. The developed electrode maintains good sensitivity for detecting BCN, despite the presence of potential interferents like organic compounds and metal ions. This sensor is stable, repeatable, and reproducible in oxidizing BCN. Real sample (tablets) analysis was done using DPV method demonstrates a favorable recovery rate.

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