Mei Yuli, Yang Shuo, Su Minghui, Xie Jianjun, Huang Shengfeng, Jiang Zhengjin, Huang Yang
Guangzhou Municipal and Guangdong Provincial Key Laboratory of Molecular Target & Clinical Pharmacology, The NMPA, State Key Laboratory of Respiratory Disease, School of Pharmaceutical Sciences, Guangzhou Medical University, Guangzhou 511436, China.
Guangzhou Customs Technology Centre, Guangzhou 510623, China.
Anal Methods. 2025 Jul 3;17(26):5400-5411. doi: 10.1039/d5ay00704f.
A nitrogen-doped carbon dots (N-CDs)-based fluorescent sensor was developed for ultrasensitive and selective detection of mercury ions (Hg) in complex matrices, such as (Burk.) F. H. Chen (Sanqi). The synthesized N-CDs exhibited intense blue fluorescence (quantum yield: 35%) with an ultra-small size of 1.93 ± 0.53 nm. Leveraging dynamic quenching mechanisms, the sensor achieved a linear detection range of 0-50 μM for Hg and an exceptionally low limit of detection (LOD) of 0.2825 nM, outperforming existing CD-based sensors. The N-CDs demonstrated remarkable selectivity for Hg in the presence of interfering ions and complex herbal components. Hg in Sanqi samples was quantified by fluorescence analysis (25.5-26.8 μg kg, RSD < 2.0%) and cross-validated Inductively Coupled Plasma Mass Spectrometry (ICP-MS) (24.8-26.2 μg kg, RSD < 1.0%), demonstrating N-CDs' reliability for precise Hg detection. Additionally, the N-CDs exhibited excellent biocompatibility and were successfully applied for cellular imaging in A549 cells, showcasing their dual functionality in environmental monitoring and biomedical diagnostics.
开发了一种基于氮掺杂碳点（N-CDs）的荧光传感器，用于超灵敏和选择性检测复杂基质中的汞离子（Hg），如三七（Panax notoginseng (Burk.) F. H. Chen）。合成的N-CDs呈现出强烈的蓝色荧光（量子产率：35%），尺寸超小，为1.93±0.53纳米。利用动态猝灭机制，该传感器对Hg的线性检测范围为0-50μM，检测限（LOD）极低，为0.2825 nM，优于现有的基于碳点的传感器。在存在干扰离子和复杂草药成分的情况下，N-CDs对Hg表现出显著的选择性。通过荧光分析对三七样品中的Hg进行定量（25.5-26.8μg/kg，相对标准偏差<2.0%），并通过电感耦合等离子体质谱法（ICP-MS）进行交叉验证（24.8-26.2μg/kg，相对标准偏差<1.0%），证明了N-CDs在精确检测Hg方面的可靠性。此外，N-CDs表现出优异的生物相容性，并成功应用于A549细胞的细胞成像，展示了它们在环境监测和生物医学诊断中的双重功能。
