Dual-mode nanoprobe for selective detection of arsenite based on yellow fluorescent carbon dots

Arsenic is a toxic heavy metal element and widely distributed in nature, however, long-term exposure to low doses of arsenite (As3+) is harmful to human health. Therefore, it is particularly important to establish a quick and sensitive detection method for As3+ in the environment. Yellow fluorescent carbon dots were prepared by hydrothermal method with rhodamine B and citrate as precursors. The RbB-CDs were purified by thin layer chromatography and chromatographic column. The good line ranges of 0–5 μg/L and 10–50 μg/L As3+ were obtained with low detection limits of 0.75 μg/L and 5.00 μg/L based on fluorescence, respectively, while a good line range of 0–50 μg/L was obtained with a low detection limit of 3.03 μg/L based on UV absorbance. Furthermore, static quenching was verified to work in the quenching process of As3+ towards RbB-CDs fluorescence. In addition, the yellow fluorescent nanoprobe was employed to determine the As3+ content in tap water, lake water, and river water samples. It showed good potential to detect As3+ in the environment.