Molecularly Imprinted Fluorescent Sensor Based on SiO₂ Nanoparticles and BODIPY for Detection of Histamine in Marine Samples

The detection of histamine (HA) is critical due to its significant implications for food safety, public health, and regulatory compliance. In this study, we developed a molecularly imprinted fluorescent (MI-FL) “turn-on” sensor IBCP based on SiO2 nanoparticles and BODIPY for the selective detection of HA in complex marine samples. A Schiff-base compound formed between BODIPY and HA was synthesized and employed simultaneously as both the fluorescent monomer and the template molecule. The sensor was constructed by using silica nanoparticles as the core and epoxysilane as a cross-linker to create highly specific recognition cavities through covalent imprinting after template removal. The MI-FL sensor IBCP exhibited a linear fluorescence response to HA concentrations ranging from 0.004 to 0.9 mg/mL, with a low limit of detection of 0.002 mg/mL. When applied to various marine samples─including silvery pomfret, mantis shrimp, scallops, gazami crab, and seawater─it demonstrated satisfactory recoveries of HA ranging from 92.3 to 116.8%, with relative standard deviations below 8.1%. The accuracy and reliability of the method were further validated by comparison with commercial detection kits. This Schiff-based MI-FL sensing study provides a universal method for HA detection in complicated matrices.