Screen‐Printed Carbon Electrodes Modified with Poly(amino acids) for the Simultaneous Detection of Vitamin C and Paracetamol

Abstract

Electrochemical polarization provides a practical means to enhance the typically sluggish electrochemical kinetics of screen‐printed electrodes. This study introduces an electrochemically deposited poly(amino acid) modification on screen‐printed carbon electrodes (SPCE) for the concurrent detection of Vitamin C (VC) and Paracetamol (PA). The poly(amino acid)‐modified sensor not only addresses the issue of peak potential overlap between VC and PA but also enhances the electrochemical responses for both analytes. For example, Poly(L–Cysteine)‐modified SPCE exhibited a linear concentration range of 1.00 to 107.14 μM for VC, with a detection limit of 0.37 μM, and a linear concentration range of 0.10 to 10.71 μM for PA, with a detection limit of 0.033 μM. In practical applications, this device successfully detected VC and PA simultaneously in VC Yinqiao tablets, a Chinese‐Western pharmaceutical formulation. The experimental results were satisfactory, with recovery values ranging from 95.13 % to 106.58 % for VC and 95.56 % to 104.12 % for PA, achieved through the standard addition technique applied to the pharmaceutical formulation. The poly(amino acid)‐modified SPCE demonstrates heightened sensitivity, lower detection limits, exceptional anti‐interference properties, and high reproducibility. These qualities hold significant promise for future advancements in drug detection.