Xu Yating, Lei Tingting, Zhu Pan, Zhao Shaojing, Xiao Jiafu, Lan Minhuan
College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, PR China.
Hunan Provincial Key Laboratory for Synthetic Biology of Traditional Chinese Medicine, School of Pharmaceutical Sciences, Hunan University of Medicine, Huaihua 418000, PR China.
Spectrochim Acta A Mol Biomol Spectrosc. 2025 Dec 15;343:126580. doi: 10.1016/j.saa.2025.126580. Epub 2025 Jun 18.
Accurate and sensitive detection of mercury ions (Hg) and thiram is essential for food safety monitoring and environmental protection. Here, an "on-off-on" fluorescent probe based on red-emitting carbon dots (CDs) was fabricated for sequential detection of Hg and thiram. The CDs exhibited red fluorescence at λ = 676 nm with a narrow full width at half maximum of 25 nm. Upon exposure to Hg, the fluorescence was significantly quenched due to the static quenching mechanism, achieving a limit of detection (LOD) of 25 nM. Notably, upon the addition of thiram, the quenched fluorescence of CDs was recovered due to the strong chelation between thiram and Hg, thereby enabling sensitive detection of thiram with a LOD of 4.80 nM. The approach was successfully validated using real water samples spiked with Hg and thiram. The recovery rates were between 97.16 % and 113.83 %, with relative standard deviations below 9.11 %. This study presents a simple, eco-friendly, and effective approach for the sensitive screening of trace contaminants in complex matrices.
准确且灵敏地检测汞离子（Hg）和福美双对于食品安全监测和环境保护至关重要。在此，制备了一种基于发红光碳点（CDs）的“关-开-关”荧光探针，用于依次检测Hg和福美双。这些CDs在λ = 676 nm处呈现红色荧光，半高宽为25 nm，较窄。暴露于Hg时，由于静态猝灭机制，荧光显著猝灭，检测限（LOD）达到25 nM。值得注意的是，加入福美双后，由于福美双与Hg之间的强螯合作用，CDs猝灭的荧光得以恢复，从而能够以4.80 nM的LOD灵敏地检测福美双。该方法通过添加Hg和福美双的实际水样成功得到验证。回收率在97.16%至113.83%之间，相对标准偏差低于9.11%。本研究提出了一种简单、环保且有效的方法，用于在复杂基质中灵敏地筛选痕量污染物。
