Carbon dots-based electrochemical and fluorescent biosensors for the detection of foodborne pathogens: Current advance and challenge

Food safety is essential for sustaining a healthy life, with foodborne pathogens representing a principal factor contributing to food safety risks, thereby posing a formidable threat to human health that cannot be overlooked. According to the U.S. Centers for Disease Control statistics, the U.S. has caused a cumulative total of more than 9.6 million foodborne illnesses, a variety of foodborne pathogens enter the human body along with eating, endangering people's physical and mental health, but also add a huge burden on society. Traditional detection techniques are time-consuming, labor-intensive, and heavily dependent on expensive equipment. Therefore, to protect people's lives and health, many scholars around the world have been exploring how to develop efficient, convenient, and low-cost foodborne pathogens detection technologies. In the process of exploration, carbon dots (CDs), as a new type of nanoparticles, have gradually become an excellent choice for pathogenic microbial detection due to their unique optical and physicochemical properties as well as low toxicity. The detection of foodborne pathogens based on CDs can be efficiently achieved through electrochemical or fluorescent biosensors. This review not only elucidates the preparation of CDs but also succinctly summarizes their application in CDs-based electrochemical and fluorescent biosensors for detecting foodborne pathogens. It delves into the underlying working mechanisms, outlines the advantages, and discusses the limitations of these sensors. In addition, the urgent problems that need to be solved in the practical application of CDs-based biosensors and the future exploration directions are also elaborated.