ISSN 1017-2548(Print)
ISSN 2234-8530(Online)
Volume 37, Number 10
JKCSEZ 37(10)
August 20, 1993 

Spectrophotometric enzymatic analysis and amperometric enzymatic analysis for the determinations of glucose and ethanol were studied utilizing glucose oxidase (GO) and alcohol oxidase (AO), respectively, which commonly consume O2 and produce H2O2. For the determination of glucose, H2O2 were coupled to K4Fe(CN)6 via peroxidase producing K3Fe(CN)6 whose absorbance was measured at 418 nm or whose diffusion current was measured on the glassy carbon electrode at an applied potential of -55 mV vs. Ag/AgCl (sat. KCl) reference electrode. Amperometric analysis was 1000 times more sensitive as well as 10 times better in the linear concentration range than spectrophotometric analysis. For the determination of ethanol, AO only was used for the enzymatic analysis, since K3Fe(CN)6 was completely disappeared as soon as AO was added. Either rate of H2O2 produced was amperometrically measured at ＋0.900 V or rate of O2 consumed was measured at -0.500 V vs. Ag/AgCl(sat. KCl) reference electrode.