Metal-organic frameworks-based nanozyme sensor array for the discrimination of biogenic amines and detection of histamine.

Biogenic amines (BAs) are hazardous substances found in fishery products that are closely associated with fish spoilage and threaten food safety. Traditional chromatographic methods for detecting BAs are expensive, complex, and time-consuming. In this study, we developed a nanozyme-based sensor array to efficiently discriminate between four types of BAs and sensitively detect histamine. Copper-, cerium-, and manganese-based metal-organic frameworks with excellent peroxidase-like activities were employed as sensor elements. Because the catalytic activities of metal-organic frameworks could be modified by different BAs to varying degrees, the sensor array could generate a distinct colorimetric response pattern (fingerprint) for each BA. Based on this principle, the sensor array accurately discriminated BAs over a wide concentration range (10-1000 μM). Histamine could be distinguished down to 1 μM and detected with a detection limit of 4.28 μM within 20 min. In addition, mixtures of BAs, target BAs, interfering substances, and BAs in fishery product samples were well discriminated. Furthermore, our sensor array could also effectively distinguish the freshness of fish samples. This work might offer a useful strategy for the discrimination and detection of BAs and could positively contribute to food safety and public health.