Recent development of electrochemiluminescence sensors for food analysis

Food quality and safety are closely related to human health. In the face of unceasing food safety incidents, various analytical techniques, such as mass spectrometry, chromatography, spectroscopy, and electrochemistry, have been applied in food analysis. High sensitivity usually requires expensive instruments and complicated procedures. Although these modern analytical techniques are sensitive enough to ensure food safety, sometimes their applications are limited because of the cost, usability, and speed of analysis. Electrochemiluminescence (ECL) is a powerful analytical technique that is attracting more and more attention because of its outstanding performance. In this review, the mechanisms of ECL and common ECL luminophores are briefly introduced. Then an overall review of the principles and applications of ECL sensors for food analysis is provided. ECL can be flexibly combined with various separation techniques. Novel materials (e.g., various nanomaterials) and strategies (e.g., immunoassay, aptasensors, and microfluidics) have been progressively introduced into the design of ECL sensors. By illustrating some selected representative works, we summarize the state of the art in the development of ECL sensors for toxins, heavy metals, pesticides, residual drugs, illegal additives, viruses, and bacterias. Compared with other methods, ECL can provide rapid, low-cost, and sensitive detection for various food contaminants in complex matrixes. However, there are also some limitations and challenges. Improvements suited to the characteristics of food analysis are still necessary.