Molecularly imprinted electrochemical sensors based on mesoporous silica films for the detection of Deoxynivalenol in grain

This study developed a high-performance electrochemical sensor based on mesoporous silica film (VMSF) and molecular imprinting technology (MIP) for the trace detection of deoxynivalenol (DON) in grains. The sensor was constructed by electrochemically assisted self-assembly (EASA) of vertically ordered VMSF layers on a screen-printed carbon electrode (SPCE), significantly enhancing resistance to matrix interference; reduced graphene oxide (rGO) is introduced as a conductive layer to enhance electron transfer efficiency; and arginine (Arg) is used as the functional monomer, with DON as the template molecule, to synthesize a molecularly imprinted polymer (MIP) with specific recognition cavities on the rGO/VMSF surface via electropolymerization. Under optimized conditions, the sensor exhibits excellent analytical performance for DON: the detection linear range is 0.1 to 500 ng/mL, with a detection limit as low as 0.028 ng/mL (S/N = 3), and a correlation coefficient R²=0.9927. Its high selectivity stems from the precise matching of the MIP cavities with DON molecules in terms of size, shape, and functional groups, effectively eliminating common interferents in grains. The sensor exhibits good repeatability (RSD < 2.57%) and has been successfully applied to actual wheat sample testing, with spiked recovery rates ranging from 95.73% to 100.52%, validating the method's accuracy and reliability. This sensor integrates the anti-fouling properties of VMSF, the enhanced conductivity of rGO, and the high specificity of MIP, offering high sensitivity, rapid response, ease of operation, and low cost. It provides a powerful new tool for on-site rapid screening of DON contamination in grains.