Shuji Arakawa

Flow-injection determination of glutathione with amperometric monitoring of the enzymatic reaction

Glutathione sulfhydryl oxidase is immobilized on oxirane-acrylic beads (Eupegit-C) and packed in a small column. The simple system for glutathione comprises the immobilized enzyme column and a flow-through membrane-covered platinum/silver/silver chloride electrode pair for detection of hydrogen peroxide. The calibration graph for glutathione was linear from 0.05 to 1.0 mM for 200-μl samples. The assay took 3 min. The relative standard deviation for 0.5 mM glutathione was 2% (n=10).

Calorimetric flow-injection determination of glutathione with enzyme-thermistor detector

Abstract Glutathione sulfhydryl oxidase and catalase are separately immobilized onto oxirane-acrylic beads (Eupergit-C). Both types of beads are double-layered into a small polymer column. The flow-injection analysis system for glutathione is assembled with the column and a calorimetric device for enzymatically generated heat. The calibration graph for glutathione is linear from 0.5 to 10 mM for 0.2 ml samples. The assay takes less than 6 min. The relative standard deviation for 5.0 mM glutathione is 1.2% (n = 5).