P. Na NakornM. SuphantharikaS. UdomsopagitW. SurareungchaiMahidol UniversityKing Mongkuts University of Technology Thonburi2018-07-242018-07-242003-07-01World Journal of Microbiology and Biotechnology. Vol.19, No.5 (2003), 479-485095939932-s2.0-0042413576https://repository.li.mahidol.ac.th/handle/20.500.14594/20713An amperometric L-glutamate oxidase (GLOD) electrode based on a multilayer of polymer films was developed for the high selective determination of L-glutamate. The multilayer film consisted of three layers as the following configuration i.e., inner membrane of electropolymerized 1,3-diaminobenzene, middle layer of L-GLOD entrapped in photopolymerized poly(vinylferrocene)-poly(ethylene glycol) hydrogel polymer, and outer dialysis membrane. In this manner, the sensor could eliminate interferences and was able to work at a low potential poised at +0.085 V vs. Ag/AgCl. When used in a flow injection system, the sensor responded to L-glutamate in the range 0.5-8.0 mM, with a sensitivity of 9.48 nA mM-1. The sensor was stable for 5 days of continuous uses (250 assays) and retained 60% activity after 16 days. When used to analyse the L-glutamate contents of a number of different off-the-shelf soy sauces, the sensor gave results in good agreement with the standard colorimetric method.Mahidol UniversityBiochemistry, Genetics and Molecular BiologyImmunology and MicrobiologyArticleSCOPUS10.1023/A:1025181317237