Nitrogen-doped carbon dots in food sensing: a review of detection mechanisms and applications

Ensuring food safety is an escalating global priority due to the rising risk of contamination and the necessity for meticulous monitoring of food quality. Fluorescent nanomaterials, specifically carbon dots (CDs), have garnered interest among new technologies for their potential in sensitive and speedy detection systems. Nitrogen doping has become a pivotal approach for augmenting the optical and electrical characteristics of carbon dots, owing to nitrogen's elevated electronegativity and its capacity to produce functional groups and trap states that enhance photoluminescence and sensor efficacy. Nitrogen-doped carbon dots (N-CDs) have exceptional biocompatibility, stability, and adjustable fluorescence, rendering them suitable for food safety applications. This review article presents an overview of the synthesis methods for N-CDs and their application in food sensing. Particular uses encompass the identification of heavy metals, antibiotics, food colourants, and spoilage indicators. The review addresses contemporary obstacles in synthesis, reproducibility, and practical integration, while delineating future directions for the advancement of N-CD-based sensing in food safety monitoring.