A simple and inexpensive glucose oxidase substrate system for enzyme immunoassay.

A simple and inexpensive glucose oxidase substrate system was developed for enzyme immunoassay. This system is based on the formation of a coloured complex between polyvinyl alcohol or starch and iodine produced from iodide in the presence of hydrogen peroxide generated by the glucose oxidase reaction. The rate of iodine production was enhanced by the supplementation of molybdate. In an enzyme immunoassay for anti-Salmonella antibodies using glucose oxidase as the indicator enzyme, the molybdate-enhanced polyvinyl alcohol- and starch-glucose-iodide substrate systems were as sensitive as a conventional glucose oxidase assay system employing horseradish peroxidase as a secondary enzyme and a suitable hydrogen-donating chromogen.