Enzyme sensing based on a controllable oxidation reaction.
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.
Sheng
Ruilong
R
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.
Ma
Jingjin
J
Wang
Pengfei
P
Liu
Weimin
W
Wu
Jiasheng
J
Li
Huaping
H
Zhuang
Xiaoqing
X
Zhang
Hongyan
H
Wu
Shikang
S
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
D004800:Enzymes, Immobilized; D013438:Sulfhydryl Compounds; D005980:Glutathione Reductase