N-B co-doped hollow mesoporous carbon sphere support PEDOT-CH₂OH derivative molecularly imprinted electrochemical...

Molecularly imprinted electrochemical sensors (MIECS) are promising for selective analysis in complex food matrices, but their performance is often limited by insufficient signal transmission and restricted accessibility of recognition sites. In this work, a MIECS was constructed for sodium dehydroacetate (Na-DHA) detection using nitrogen-boron co-doped hollow mesoporous carbon spheres (N-B-HMCS) as the conductive scaffold and hydroxymethyl-functionalized EDOT (EDOT-CH₂OH) as the functional monomer. The hollow mesoporous carbon scaffold facilitated electron transfer and molecular transport, while the EDOT-CH₂OH-derived imprinted layer provided accessible recognition sites for Na-DHA. Under optimized conditions, the proposed sensor exhibited a wide linear range of 0.003-100 μM and a low detection limit of 0.87 nM. The sensor also showed satisfactory selectivity, anti-interference capability, repeatability, reproducibility, and short-term storage stability. Satisfactory recoveries of 98.46%-103.43% were obtained in six representative spiked food samples, including soy sauce, fruit juice, canned fruit, shiitake mushroom sauce, milk, and pastry. The analytical results were further compared with those obtained using an HPLC reference method. These results indicate that the proposed N-B-HMCS@MIP sensor provides a sensitive and promising electroanalytical platform for Na-DHA determination in food safety analysis.