title: Enzyme sensing based on a controllable oxidation reaction.
abstract: We developed a new method for glutathione reductase (GR) enzyme sensing via a metal-controlled spontaneous oxidation reaction. A new complex HgL, composed of 3-benzothiazoliny-7-N,N-diethylaminocoumarin (L) and HgCl2, was used as an example for illustration. It was found that ligand L was released from complex HgL by a ligand exchange process in the presence of GSH, which was enzymatic reduced from GSSG in the presence of NADH. Subsequently, free ligand L was spontaneously oxidated to a laser dye (coumarin-6) with both fluorescence enhancement and color change. A good linear relationship between fluorescent intensity and GSH concentrations (in the range of 10-40 μM) elicits the potential use of HgL in GSH detection. Based on this result, complex HgL was applied to identify GR from other proteins/enzymes with good selectivity and sensitivity. HgL can also determine GR in the concentration range from 0.5 to 10 U/mL with a linear relationship. Furthermore, this novel sensing method was also expected to be a useful example for the design of other biosensing systems.
authors.affiliation: Key Laboratory of Photochemical Conversion and Optoelectronic Materials, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beiyitiao No. 2, Zhongguancun, Beijing 100190, China.
authors.forename: Ruilong
authors.initials: R
authors.lastname: Sheng
authors.forename: Jingjin
authors.initials: J
authors.lastname: Ma
authors.forename: Pengfei
authors.initials: P
authors.lastname: Wang
authors.forename: Weimin
authors.initials: W
authors.lastname: Liu
authors.forename: Jiasheng
authors.initials: J
authors.lastname: Wu
authors.forename: Huaping
authors.initials: H
authors.lastname: Li
authors.forename: Xiaoqing
authors.initials: X
authors.lastname: Zhuang
authors.forename: Hongyan
authors.initials: H
authors.lastname: Zhang
authors.forename: Shikang
authors.initials: S
authors.lastname: Wu
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation*; D003124:Colorimetry / Q000295:instrumentation*; D004800:Enzymes, Immobilized / Q000737:chemistry; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005980:Glutathione Reductase / Q000737:chemistry*; D010084:Oxidation-Reduction; D013050:Spectrometry, Fluorescence / Q000295:instrumentation*; D013438:Sulfhydryl Compounds / Q000032:analysis* / Q000737:chemistry
chemical_list: D004800:Enzymes, Immobilized; D013438:Sulfhydryl Compounds; D005980:Glutathione Reductase