Aptamer-Based Quartz Crystal Microbalance Biosensor for Histamine

Histamine is a biogenic amine commonly associated with food spoilage and allergic reactions, making its rapid and accurate detection critical for food safety.This study aimed to develop a quartz crystal microbalance (QCM) biosensor using a histamine-specific aptamer as the recognition element.The thiol-modified aptamer was immobilized on the gold electrode of the quartz crystal, and the surface was characterized by scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDS).Adsorption behavior was investigated through equilibrium binding experiments and Langmuir isotherm analysis, while key variables-such as sample pH, aptamer concentration, and immobilization timewere optimized to enhance sensor performance.The biosensor exhibited a linear response in the range of 0.01-1 mg/L (R² = 0.995) and a limit of detection of 0.0071 mg/L.It demonstrated high selectivity, with selectivity factors exceeding 15 against structurally related analogs, as well as good repeatability and recovery rates (99-109%) when tested with fish sauce samples.These findings indicate that the developed aptamer-QCM biosensor is a practical, selective, and sensitive platform for histamine detection in food safety applications.