title: Sensitive and selective sensor for biothiols in the cell based on the recovered fluorescence of the CdTe quantum dots-Hg(II) system.
abstract: Herein, a sensitive and selective sensor for biothiols based on the recovered fluorescence of the CdTe quantum dots (QDs)-Hg(II) system is reported. Fluorescence of QDs could be quenched greatly by Hg(II). In the presence of biothiols, such as glutathione (GSH), homocysteine (Hcy), and cysteine (Cys), however, Hg(II) preferred to react with them to form the Hg(II)-S bond because of the strong affinity with the thiols of biothiols rather than quenching the fluorescence of the QDs. Thus, the fluorescence of CdTe QDs was recovered. The restoration ability followed the order GSH > Hcy > Cys due to the decreased steric hindrance effect. A good linear relationship was obtained from 0.6 to 20.0 micromol L(-1) for GSH and from 2.0 to 20.0 micromol L(-1) for Cys, respectively. The detection limits of GSH and Cys were 0.1 and 0.6 micromol L(-1), respectively. In addition, the method showed a high selectivity for Cys among the other 19 amino acids. Furthermore, it succeeded in detecting biothiols in the Hela cell.
authors.affiliation: State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Graduate School of the Chinese Academy of Sciences, Changchun, Jilin, 130022, China.
authors.forename: Bingyan
authors.initials: B
authors.lastname: Han
authors.forename: Jipei
authors.initials: J
authors.lastname: Yuan
authors.forename: Erkang
authors.initials: E
authors.lastname: Wang
mesh_terms: D019187:Cadmium Compounds / Q000737:chemistry*; D045744:Cell Line, Tumor; D005453:Fluorescence; D006367:HeLa Cells; D006801:Humans; D017669:Mercury Compounds / Q000737:chemistry*; D010087:Oxides / Q000737:chemistry*; D045663:Quantum Dots; D013050:Spectrometry, Fluorescence; D013438:Sulfhydryl Compounds / Q000737:chemistry*; D013691:Tellurium / Q000737:chemistry*
chemical_list: D019187:Cadmium Compounds; D017669:Mercury Compounds; D010087:Oxides; D013438:Sulfhydryl Compounds; C019468:mercuric oxide; D013691:Tellurium; C028337:cadmium telluride