Molecular Imprinting With Polyaniline on ENIG Finish PCB Electrodes for Electrochemical Detection of Melamine

Electrochemical sensors based on molecularly imprinted polymers (MIPs) leverage predetermined recognition sites (templates) for binding of analytes of interest, resulting in high selectivity and sensitivity, ease of preparation and portability. The choice of monomers and cross-linkers depends heavily on choice of substrate for in situ electropolymerization, and damage to the template caused by methods used to wash away the analyte after formation of MIP on the substrate result in limitations for batch-compatible synthesis methods of such sensors. In this paper, we describe a method to utilize low-cost ENIG finish PCB electrodes as electrochemical sensor substrates for detection of melamine, a common adulterant in milk, through molecular imprinting in polyaniline (PANI). The MIP was synthesized using chemical synthesis method and drop-casted onto the electrodes, thus realizing a low-cost fabrication method. Preliminary results for melamine detection are reported, along with performance evaluation of various synthesis methods to synthesize polyaniline.