Li Zhuoying, Zhou Linan, Zhang Fang, Yang Huiyi, Guo Lihua, Chai Fang
Key Laboratory of Photochemical Biomaterials and Energy Storage Materials, Heilongjiang Province, Key Laboratory for Photonic and Electronic Bandgap Materials, Ministry of Education, College of Chemistry and Chemical Engineering, Harbin Normal University, Heilongjiang Province, China.
Purple Mountain Laboratories, Nanjing, Jiangsu Province, China.
Spectrochim Acta A Mol Biomol Spectrosc. 2025 Dec 15;343:126536. doi: 10.1016/j.saa.2025.126536. Epub 2025 Jun 4.
Heavy metals adversely affect the environment, ecosystems, and human health. The effective detection and treatment of heavy metals has become a major global concern. Herein, calcium and nitrogen co-doped carbon dots (E-CDs) were developed using cheap kitchen waste eggshells as precursors, and utilized as dual-mode fluorimetric/colorimetric sensor for the multivariate detection of Hg and Ag. The E-CDs exhibited yellow emission at 420 nm excited at 567 nm, with a quantum yield of 15.49% and lifetime of 12.92 μs. The multivariate detection of Hg and Ag can be achieved selectively by distinguishing via dual-mode respectively. The limit of detection (LOD) for Hg reached 11.28 nM, while the Ag can be determined by fluorimetric/colorimetric dual-mode with LODs of 128.23 nM and 1.02 μM, respectively. Remarkably, the E-CDs integrated with a smartphone-based paper sensor supported by RGB analysis achieved the detection of Hg and Ag with LODs of 56.2 nM and 90.96 nM, respectively. Notably, the recoveries in real samples attained 96.3-105.7% with excellent environmental tolerance. Furthermore, a logic gate circuit was developed to support the potential practical intelligent application. This work highlighted a cost-effective, multi-functional sensing strategy with significant potential for monitoring heavy metal contaminants in environmental and food safety applications.
重金属对环境、生态系统和人类健康产生不利影响。重金属的有效检测和处理已成为全球主要关注点。在此，以廉价的厨房废弃物蛋壳为前驱体，制备了钙氮共掺杂碳点（E-CDs），并将其用作荧光/比色双模式传感器，用于汞和银的多变量检测。E-CDs在567nm激发下于420nm处呈现黄色发射，量子产率为15.49%，寿命为12.92μs。通过分别采用双模式进行区分，可选择性地实现汞和银的多变量检测。汞的检测限（LOD）达到11.28nM，而银可通过荧光/比色双模式分别以128.23nM和1.02μM的检测限进行测定。值得注意的是，结合基于RGB分析的智能手机纸基传感器的E-CDs分别实现了对汞和银的检测，检测限分别为56.2nM和90.96nM。值得注意的是，实际样品中的回收率达到96.3-105.7%，具有出色的环境耐受性。此外，还开发了一种逻辑门电路以支持潜在的实际智能应用。这项工作突出了一种具有成本效益的多功能传感策略，在环境和食品安全应用中监测重金属污染物方面具有巨大潜力。
