Selective and sensitive simultaneous detection of tartrazine and Hg2+based on N-doped yellow-green fluorescent carbon dots

Tartrazine preferred in food and textile industries, but excessive consumption threats human health. Due to toxicity, non-biodegradability, and trace accumulation in the food chains, Hg2+ has attracted people's attention. Thus, it is important to detect tartrazine and Hg2+ with sensitivity way. Using VB2 and citrate as precursors, yellow-green fluorescent carbon dots were prepared by hydrothermal method. The N-CDs were purified by dialysis, thin layer chromatography and chromatographic column. Excellent linear ranges of 0.25-5 mu M and 5-50 mu M of tartrazine were obtained with low detection limits 34.98 nM, while good linear ranges of 0.25-5 mu M and 10-50 mu M of Hg2+ with low detection limits 29.64 nM, respectively. In addition, the quenching mechanisms of targets to the fluorescent of N-CDs were illuminated. Furthermore, the nanoprobe was efficiently applied to determine the content of tartrazine in carbonated drink, fruit jelly and sugar samples, and Hg2+ in tap water, lake water, and river water samples. It showed great potential to detect tartrazine and Hg2+.

Automated summary

In this study, yellow-green fluorescent carbon dots were prepared using VB2 and citrate as precursors, and they showed great potential for detecting tartrazine and Hg2+. The N-CDs were purified and achieved excellent linear ranges and low detection limits. The quenching mechanisms of N-CDs fluorescence were also illuminated, and the nanoprobe was successfully applied to determine the content of tartrazine and Hg2+ in different samples.