Coral-like silver citrate as robust laccase mimetics in a novel colorimetric aptasensor for sensitive and highly selective detection of histamine in food
Jianli Zhou, Junjun Wang, Xiaohuan Huang, Lian Xia, Han Tao, Yuangen Wu
Abstract
The colorimetric methods for histamine detection still face some challenges in accuracy and stability. Herein, a novel colorimetric aptasensor for sensitive and highly selective detection of histamine was developed based on the enhancement of silver citrate (AgCit) laccase-mimic activity. It has been confirmed that H2 aptamer enhances the affinity of AgCit to the chromogenic substrate, and promotes the generation of semiquinone radical in the laccase-mimic catalytical system. The color change of the sensing solution can be distinguished by the naked eye, and easily converted to the corresponding RGB value by a smartphone for the quantitative and rapid detection of histamine. The aptasensor has a limit of detection (LOD) as low as 27 μg L −1 , and maintains high selectivity for histamine in the presence of other competitive substances. It is strongly believed that the design of a colorimetric aptasensor can provide a simple and versatile platform for histamine detection in food.