Premium
Amperometric Biosensor for Glutathione Based on Osmium‐Polyvinylpyridine Gel Polymer and Glutathione Sulfhydryl Oxidase
Author(s) -
Mao Lanqun,
Yamamoto Katsunobu
Publication year - 2000
Publication title -
electroanalysis
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.574
H-Index - 128
eISSN - 1521-4109
pISSN - 1040-0397
DOI - 10.1002/(sici)1521-4109(200005)12:8<577::aid-elan577>3.0.co;2-9
Subject(s) - amperometry , chemistry , glutathione , hydrogen peroxide , cyclic voltammetry , biosensor , osmium , detection limit , glucose oxidase , glutathione disulfide , flow injection analysis , chromatography , nuclear chemistry , inorganic chemistry , electrode , electrochemistry , catalysis , organic chemistry , biochemistry , enzyme , ruthenium
A new amperometric biosensor based on glutathione sulfhydryl oxidase (GSH‐SOx) and osmium‐polyvinylpyridine gel polymer (Os‐gel‐HRP) bilayer film modified glassy carbon (GC) electrode was demonstrated for glutathione (GSH) and glutathione disulfide (GSSG). Os‐gel‐HRP was applied at glassy carbon (GC) electrode with a surface coverage of 7.1 µL/cm 2 to sense hydrogen peroxide based on horseradish peroxide (HRP) catalytic reaction mediated by osmium. GSH‐SOx was immobilized at Os‐gel‐HRP cast coated GC electrode with an approximate surface coverage of 7 U/cm 2 by cross‐linking with BAS‐GSH‐SOx in glutaraldehyde vapor for 5 min. The resultant bienzyme‐based sensor was tested toward GSH and GSSG with techniques of cyclic voltammetry (CV), flow cell amperometry and flow injection analysis (FIA). The sensor was polarized at 0.0 V (versus Ag/AgCl, 3M KCl) electrode for the detection of GSH and GSSG in a flow system at a flow rate of 6 µL/min. Linear response to GSH and GSSG in a concentration range from 1 µM to 200 µM and 2 µM to 120 µM was obtained at the sensor with a sensitivity of 1.195 nA/µM and 0.60 nA/µM for GSH and GSSG, respectively. The dependence of current response on pH value of the buffer and operating potential was also tested and optimized.