Efficient Synthesis of Highly Photo‐stable N‐doped Carbon Quantum Dots and their Applications in Detection and Cellular Imaging of Mercury Ions
Shunwei Wu, Yongzheng Yin, Chunyan Sun, Weijun Song
Abstract
Abstract In this work, the nitrogen doped carbon quantum dots (N‐CQDs) were synthesized by a simple microwave hydrothermal method using citric acid (carbon source) and urea (dopant) and optimized the preparation conditions by orthogonal tests. The synthesized N‐CQDs emitted a bright blue fluorescence with specific selectivity for Hg 2+ . The study revealed a static quenching mechanism of Hg 2+ on the N‐CQDs. The N‐CQDs showed good linear correlation in the range of 0–120 μM for the detection of Hg 2+ with a low detection limit of 22.50 nM. We also demonstrated the suitability of the N‐CQDs for the detection of Hg 2+ in tap water and industrial wastewater with spiked recoveries of 97.56 %–103.58 %. In addition, the synthesized N‐CQDs with high fluorescence intensity, good optical stability and biocompatibility were successfully applied to fluorescent inks and imaging of Hela cells. This indicated that the synthesized N‐CQDs have promising applications in Hg 2+ detection, bioimaging, and fluorescence anti‐counterfeiting.