Recent progress in photoelectrochemical sensors to quantify pesticides in foods: Theory, photoactive substrate selection, recognition elements and applications

Pesticides are essential in modern agriculture for pest control, but indiscriminate use increases concerns about food safety. It is, therefore, necessary to develop fast and effective methods for determining pesticides in food samples and water. Over the last two decades, photoelectrochemical (PEC) biosensors have emerged as promising tools in the analytical field for the detection of various pesticides. In this review, the fundamentals of PEC biosensors are introduced, including the basic theory of the PEC biosensors, detection system, and different photoactive substrates. Furthermore, over the past five years, a systematic overview of the recent advances of the emerging PEC biosensors for pesticide monitoring in foodstuffs is presented, with a particular emphasis on enzyme-based, nucleic acid-based, molecularly imprinted polymers (MIPs)-based, and mixed recognition materials-based PEC biosensors. In addition to highlighting the applications and advantages of biosensors in the real world, as well as exploring their current challenges and prospects.