title: Carbon dots-based fluorescent probe for "off-on" sensing of Hg(II) and I⁻.
abstract: Herein, we report a simple, one-step reflux method for synthesis of photoluminescent carbon dots (CDs) using citric acid as the carbon source and diethylenetriamine (DETA) as the surface passivation reagent along with a high quantum yield (82.40%), the fluorescence intensity of the CDs was found to be effectively quenched by Hg(II) ions. Upon addition of I(-) to the CDs/Hg(II) complex dispersion, the fluorescence intensity of the CDs was significantly recovered. Furthermore, we developed an "off-on" fluorescence assay for the detection of I(-) using CDs/Hg(II) as a fluorescence probe. This probe enables the selective detection of Hg(II) with a linear range of 0-80 μM and a limit of detection is 0.201 µM and a limit of detection about I(-) is 0.234 µM with a linear range of 0-70 μM. Most importantly, the sensors can be successfully applied to the determination of Hg(II) and I(-) in real lake water and urine of cattles, the "off-on" sensor demonstrates high selectivity, repeatability, stability, which offer this CDs-based "off-on" fluorescent sensor a promising platform for environmental and biological sensing applications.
authors.affiliation: Guangdong Provincial Engineering Technology Research Center for Optical Agriculture, College of Materials and Energy, South China Agricultural University, Guangzhou 510642, PR China.
authors.forename: Jiangling
authors.initials: J
authors.lastname: He
authors.affiliation: Guangdong Provincial Engineering Technology Research Center for Optical Agriculture, College of Materials and Energy, South China Agricultural University, Guangzhou 510642, PR China.
authors.forename: Haoran
authors.initials: H
authors.lastname: Zhang
authors.affiliation: Guangdong Provincial Engineering Technology Research Center for Optical Agriculture, College of Materials and Energy, South China Agricultural University, Guangzhou 510642, PR China.
authors.forename: Jinliang
authors.initials: J
authors.lastname: Zou
authors.affiliation: Guangdong Provincial Engineering Technology Research Center for Optical Agriculture, College of Materials and Energy, South China Agricultural University, Guangzhou 510642, PR China. Electronic address: tliuyl@scau.edu.cn.
authors.forename: Yingliang
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Guangdong Provincial Engineering Technology Research Center for Optical Agriculture, College of Materials and Energy, South China Agricultural University, Guangzhou 510642, PR China.
authors.forename: Jianle
authors.initials: J
authors.lastname: Zhuang
authors.affiliation: Guangdong Provincial Engineering Technology Research Center for Optical Agriculture, College of Materials and Energy, South China Agricultural University, Guangzhou 510642, PR China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Xiao
authors.affiliation: Guangdong Provincial Engineering Technology Research Center for Optical Agriculture, College of Materials and Energy, South China Agricultural University, Guangzhou 510642, PR China. Electronic address: tleibf@scau.edu.cn.
authors.forename: Bingfu
authors.initials: B
authors.lastname: Lei
mesh_terms: D000818:Animals; D002244:Carbon / Q000737:chemistry*; D002417:Cattle; D005456:Fluorescent Dyes / Q000737:chemistry*; D007454:Iodides / Q000032:analysis* / Q000097:blood*; D060106:Lakes / Q000032:analysis; D057230:Limit of Detection; D008628:Mercury / Q000032:analysis* / Q000097:blood*; D045663:Quantum Dots / Q000737:chemistry*; D013050:Spectrometry, Fluorescence / Q000379:methods
chemical_list: D005456:Fluorescent Dyes; D007454:Iodides; D002244:Carbon; D008628:Mercury
keywords: Carbon dot; Fluorescence; Off-On; Sensor