title: Fluorescence sensing of chromium (VI) and ascorbic acid using graphitic carbon nitride nanosheets as a fluorescent "switch".
abstract: Using graphitic carbon nitride (g-C3N4) nanosheets, an effective and facile fluorescence sensing approach for the label-free and selective determination of chromium (VI) (Cr(VI)) was developed. The fluorescence of the solution of g-C3N4 nanosheets was quenched effectively by Cr(VI) via the inner filter effect. Under optimal conditions, a wide detection linear range for Cr(VI) was found to be from 0.6 μM to 300 μM with a limit of detection (LOD) of 0.15 μM. In addition, the fluorescence of the solution of g-C3N4 nanosheets-Cr(VI) could be sensitively turned on in the presence of a reductant such as ascorbic acid (AA) via an "on-off-on" fluorescence response through the oxidation-reduction between Cr(VI) and AA. And a wide detection linear range for AA was found to be from 0.5 μM to 200 μM with an LOD of 0.13 μM. Furthermore, the proposed method has the potential application for detection of Cr(VI) in lake waters and AA in biological fluids.
authors.affiliation: Department of Chemistry and the MOE Key Laboratory of Spectrochemical Analysis & Instrumentation, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China.
authors.forename: Mingcong
authors.initials: M
authors.lastname: Rong
authors.affiliation: Department of Chemistry and the MOE Key Laboratory of Spectrochemical Analysis & Instrumentation, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China.
authors.forename: Liping
authors.initials: L
authors.lastname: Lin
authors.affiliation: Department of Chemistry and the MOE Key Laboratory of Spectrochemical Analysis & Instrumentation, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China.
authors.forename: Xinhong
authors.initials: X
authors.lastname: Song
authors.affiliation: Department of Chemistry and the MOE Key Laboratory of Spectrochemical Analysis & Instrumentation, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China.
authors.forename: Yiru
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China.
authors.forename: Yunxin
authors.initials: Y
authors.lastname: Zhong
authors.affiliation: Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China.
authors.forename: Jiawei
authors.initials: J
authors.lastname: Yan
authors.affiliation: the First Affiliated Hospital of Xiamen University, Xiamen University, Xiamen 361005, China.
authors.forename: Yufeng
authors.initials: Y
authors.lastname: Feng
authors.affiliation: the First Affiliated Hospital of Xiamen University, Xiamen University, Xiamen 361005, China.
authors.forename: Xiuya
authors.initials: X
authors.lastname: Zeng
authors.affiliation: Department of Chemistry and the MOE Key Laboratory of Spectrochemical Analysis & Instrumentation, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China; State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen 361005, China. Electronic address: xichen@xmu.edu.cn.
authors.forename: Xi
authors.initials: X
authors.lastname: Chen
mesh_terms: D001205:Ascorbic Acid / Q000737:chemistry / Q000302:isolation & purification*; D015374:Biosensing Techniques; D002857:Chromium / Q000737:chemistry / Q000302:isolation & purification*; D005453:Fluorescence; D006108:Graphite / Q000737:chemistry; D006801:Humans; D053758:Nanoparticles / Q000737:chemistry; D009570:Nitriles / Q000737:chemistry; D014874:Water Pollutants, Chemical / Q000737:chemistry / Q000302:isolation & purification*
chemical_list: D009570:Nitriles; D014874:Water Pollutants, Chemical; D002857:Chromium; C011206:cyanogen; D006108:Graphite; D001205:Ascorbic Acid
keywords: AA; Cr(VI); Inner filter effect (IFE); On–off–on fluorescence sensing; g-C(3)N(4) nanosheets