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

Graphical Poly(amino acid)-modified screen-printed carbon electrodes were prepared for the concurrent detection of Vitamin C (VC) and Paracetamol (PA). In practical applications, the device successfully detected VC and PA simultaneously in VC Yinqiao tablets, a Chinese-Western pharmaceutical formulation. 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.