A molecularly imprinted electrochemical sensor for detection of bisphenol A based on dendritic Pt-Pd bimetallic nanoparticles and g-C3N4 nanocomposite.

The development of a novel molecularly imprinted electrochemical sensor for the sensitive and selective detection of bisphenol A (BPA) is reported, based on a nanocomposite comprising dendritic Pt-Pd bimetallic nanoparticles and graphitic carbon nitride (Pt-Pd NPs/g-C3N4). The molecularly imprinted polymer (MIP) was fabricated via electrochemical polymerization on Pt-Pd NPs/g-C3N4 nanocomposite modified screen-printed electrode (Pt-Pd NPs/g-C3N4/SPE) surface. The synergistic integration of porous Pt-Pd NPs and ultrathin g-C3N4 nanosheets provides a larger effective surface and enhances catalytic activity for BPA determination. The MIP film was fabricated via cyclic voltammetry on the modified electrode, employing BPA as the template molecule and pyrrole as the functional monomer. Following template removal, the resulting molecularly imprinted cavities within the MIP demonstrated high specificity for BPA recognition. The fabricated MIP-based electrochemical sensor exhibited an excellent linear response and high sensitivity for BPA detection over a broad concentration range of 2-100 ng/mL, achieving a limit of detection (LOD) of 0.2 ng/mL (3σ/S) and a limit of quantification (LOQ) of 0.6 ng/mL. The MIP-based sensor exhibits outstanding specificity, reproducibility, and operational stability, thereby providing a versatile platform for rapid and ultrasensitive BPA detection-a critical capability for ensuring environmental safety and protecting public health.