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

Abstract

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 μM and 5–50 μM of tartrazine were obtained with low detection limits 34.98 nM, while good linear ranges of 0.25–5 μM and 10–50 μM 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+.