A Colorimetric Strip for Rapid Detection and Real-Time Monitoring of Histamine in Fish Based on Self-Assembled Polydiacetylene Vesicles.

Self-assembled polydiacetylene (PDA) vesicles, with the distinct advantages of low-cost materials, simple preparation, and excellent chromatic properties, can be perfectly combined with a colorimetric strip for on-site inspection. Herein, without involving expensive reagents and instruments, a visual colorimetric strip based on well-prepared PDA vesicles was developed to analyze and monitor histamine in deep-sea fish and its canned food. The standard calorimetric card for semiquantitative detection of histamine was successfully prepared and the quantitative detection can be further realized by analyzing the gray value using ImageJ and "Color Grab" in a smart phone. After optimizing the assembly conditions, this assay exhibited a linear response to histamine within the range from 70 to 2240 ppm. With excellent stability and sensitivity, this strip can be used to monitor the quality change of canned fish at different temperatures, so that people can avoid suffering from histamine poisoning, suggesting that it holds great potential in the intelligent system for on-site detection and real-time monitoring.