Review on carbon dots in food safety applications

As a new class of promising fluorescent carbon nanomaterials, carbon dots (CDs) have been well developed in recent years for their excellent fluorescent properties, simple synthetic approaches, good biocompatibility and various detection applications, which can be expected to replace the tradition semi-quantum dots. This review aims presents the current progress in the development of CDs with an emphasis on fluorescent properties, synthetic approaches and applications in food safety. First, the fluorescent properties of CDs are briefly introduced. To seek more reasonable synthetic approaches, the characteristics of the diverse methods of CD synthesis are summarized. And then, applications of CDs as fluorescent probes in food safety are discussed, with emphasis on the determination of metal ions/anions, pesticides, veterinary drugs, bacteria, functional components and banned additives. Finally, the challenges, such as how to explain the diversity of fluorescent properties, and how to form a uniform synthesis procedure to improve the quantum yield (QY), for CDs are presented. Although CDs have found many applications in food safety, it is still a challenge to detect a specific target in complex samples. Therefore, combination with other biochemistry technology to exploit novel ligands against the specific target with high binding affinity and selectivity is vitally important for developing sensitive and specific sensing probes in the future.