Unique Approach To Develop Carbon Dot-Based Nanohybrid Near-Infrared Ratiometric Fluorescent Sensor for the Detection of Mercury Ions

• DOI: 10.1021/acs.analchem.7b01443
• Publication Date: 2017-07-01T15:18:19Z
• Authors: Jingjin Zhao; Mengjiao Huang; Liangliang Zhang; Mengbing Zou; Dongxia Chen; Yong Huang; Shulin Zhao
• Keywords: Ions; Spectrophotometry, Infrared; Quantum Dots; Mercury; 02 engineering and technology; 0210 nano-technology; Carbon; Fluorescent Dyes; Nanocomposites

The ratiometric fluorescence assay, which can eliminate the external effects, has attracted great attention. In this work, a carbon dot (CD)-based nanohybrid dual-emission system was simply prepared by a unique approach of solvothermal treating corn bract and used as a ratiometric fluorescent sensor for Hg2+ detection. Under a single excitation, the obtained nanohybrid sensor had two emission bands around 470 and 678 nm, which may originate from the intrinsic structure of CDs and chlorophyll-derived porphyrins, respectively. In the presence of Hg2+, the fluorescence at 678 nm could be remarkably quenched, while the fluorescence intensity at 470 nm was only slightly altered. The fluorescence intensity ratio at 470 and 678 nm exhibited a good linear relationship in the Hg2+ concentration range from 0 to 40 μM with a detection limit of about 9.0 nM. It also had a satisfying assay performance in serum and river water samples. The prepared CD-based nanohybrid sensor here may hold the further potential applications in biomedicine study, environmental protection, and food safety.