Facile synthesis of tomato-based carbon nanodots and its utilization in sensitive detection of tartrazine

Carbon nanodots (CDs) with superior fluorescence performance were obtained by hydrothermal method using tomatoes as raw materials. When the ultraviolet absorption band of tartrazine and the fluorescence spectrum of CDs have complementary overlaps, the fluorescent internal filter effect (IFE) occurred. Furthermore, the degree of quenching of fluorescence intensity of CDs has an excellent linear correlation with tartrazine concentration. And based on this principle, a method for detecting tartrazine was established. As the decrease of fluorescence intensity, tartrazine can be measured in the linear range of 0.1 μM–40 μM. The detection limit is 39 nM, and the recovery rate is 90.7%～114.5%. The established protocol was also effectively employed to assay tartrazine in beverage samples, indicating that it has great potential for food color analysis.