Fabrication of a Molecular Imprinted Polyacrylonitrile Engraved Graphite Electrode for Detection of Formalin in Food Extracts

Formalin is extensively used by traders to preserve various food items like fish and mushrooms, but it has serious health hazards. Detection of formalin content in foods is a challenging problem and in the proposed work, an electrochemical sensor based on a molecular imprinted polymer of acrylonitrile over graphite platform (MiPAN@GP electrode) is pioneered for the recognition of formalin (FAL). The synthesized MiPAN@GP electrode material was characterized with Fourier transform infra-red (FTIR) spectroscope, UV-visible (UV-vis) spectroscope, and scanning electron microscope (SEM). The analytical performance of the electrode was evaluated by a three electrode system using cyclic voltammetry (CV) and differential pulse voltammetry (DPV). A wide linear range from 10 μM to 1000 μM with a limit of detection of 0.63 μM was obtained. The MiPAN@GP sensor exhibited various advantages, such as low cost, high repeatability, high reproducibility, long term stability, and good selectivity. The practical applicability of the MiPAN@GP electrode was tested with mushroom and fish extracts which yielded satisfactory results and high accuracy (≈ 99%) when compared with the high performance liquid chromatography (HPLC) analysis results.