A Simple and Novel Electrochemical Sensor Based on Phosphomolybdic‐Polypyrrole Film Modified Electrode for Highly Sensitive Detection of Cholic Acid

Abstract

A simpe electrochemical sensor for detection of cholic acid (CA) was designed by modifying phosphomolybdate (PMo 12 ) doped polypyrrole (PPy) film on glassy carbon electrode (PMo 12 -PPy/GCE). The electrochemical behavior of CA on PMo 12 -PPy/GCE was investigated by cyclic voltammetry and 0.5 order differential voltammetry. The results indicated that CA had high inhibitory activity toward the peak currents of PMo 12 -PPy/GCE. The reduction peak currents were linearly related to the logarithmic value of the concentration of CA from 1.0×10 7 to 1.0× 10 3 mol/L with a low detection limit of 1.0×10 8 mol/L. The developed sensor exhibited excellent sensitivity, selectivity and stability for detection of CA, and it could be successfully applied to detect the level of CA in the urine samples. Moreover, the response mechanism of CA on the PMo 12 -PPy/GCE was discussed in detail.