Development and Optimization of a Molecularly Imprinted Polymer for Electrochemical Detection of Escherichia coli

In this study, a molecularly imprinted polymer (MIP)-based electrochemical biosensor was developed for the selective detection of Escherichia coli (E. coli). The MIP recognition layer was synthesized by free-radical polymerization using MAM, AAM and VP as functional monomers with E. coli cells as the imprinting template. The MIP was immobilized onto a screen-printed electrode and evaluated using cyclic voltammetry (CV). Six MIP formulations with different MAM:AAM ratios were investigated to determine the optimal monomer composition. The optimized formulation, with an MAM:AAM ratio of 2:3:1, was evaluated over an E. coli concentration range of 10-10⁵ CFU/mL and exhibited a linear response with a slope of 4.1107 and an R² value of 0.9893 with a detection limit of 1.52 CFU/mL. The selectivity of the optimized sensor was further evaluated using Enterococcus faecalis and Pseudomonas aeruginosa, which showed lower responses than E. coli. These results indicate that the proposed MIP-based electrochemical biosensor provides preferential recognition of E. coli under the investigated conditions and demonstrates potential for bacterial detection.