Oxidases glutamate oxidase

Most studies have focused on amperometric glucose sensors based on GOx or GOx/ peroxidase [168-182]. However, a wide variety of other enzymes, including peroxidase, tyrosinase, choline oxidase, sarcosine oxidase, cholesterol oxidase, xanthine oxidase, glutamate oxidase, glutamate dehydrogenase, nitrate reductase, cholinesterase, cholesterol esterase, uricase, urease, creatinase, and creatininase, have also been employed for bioelectrosensor construction [183-203]. Representative examples are outlined in Table 2. 

The work in the biosensor industry permitted the testing and proved of stability and reproducibility of enzymes, within the conditions employed in that area. Enzymes with demonstrated stability include lactate oxidase, malate dehydrogenase, alcohol oxidase, and glutamate oxidase. 

Choline-containing phospholipids have been determined in human serum using an IMER consisting of coimmobilized phospholipase D and choline oxidase [51]. Recently, immobilized glutamate oxidase was used to determine L-glutamic acid in culture media [52],... 

Glutamate, glutamine Coimmobilized glutamate oxidase + glutaminase, Luminol-H202 CL 0.1 (J.M glutamate, 1 (J.M glutamine 44... 

Glutamate (monosodium glutamate) Food products Glutamate oxidase... 

N.E. Katsos, N.E. Labrou and Y.D. Clonis, Interaction of L-glutamate oxidase with triazine dyes selection of ligands for affinity chromatography. J. Chromatogr.B, 807 (2004) 277-285. 

Figure 8.6 The three dehydrogenase (oxidase) reactions in amino acid degradation. The enzymes are D-amino acid oxidase, glutamate dehydrogenase and proline oxidase (dehydrogenase). Biochemical details are given in Appendix 8.4.

The carrier used for this purpose consisted of a 0.1 M phosphate buffer of pH 7. The appearance of the sensing microzone is shown in Fig. 5.5.B. The oxygen optrode used was based on a 10-pm silicone rubber film containing dissolved decacyclene as indicator (S) that was fixed on a 110-pm thick polyester support (PS). A 9-pm black PTFE membrane (I) was used for optical insulation. The dye fluorescence was found to be markedly dependent on the concentration of oxygen, which exerted a quenching effect on it. The enzyme (glutamate oxidase) was immobilized on a 150-pm thick immunoaffmity membrane (E). The sensor was prepared similarly as reported by Trettnak et al. [7]. 

L-Glutamate Glutamate dehydrogenase, l-glutamate decarboxylase, l-glutamate oxidase Fruits, juices, wines, ciders Flavour enhancer... 

Almeida and Mulchandani [70] L-Glutamate Food samples L-Glutamate oxidase/on the electrode surface cross-linked with glutaraldehyde Carbon paste electrode/ +0.15 V vs. Ag/AgCl Tetrathiafulvalene (TTF)... 

Chen and Su [102] L-Glutamate L-Glutamic acid fermentation L-Glutamate oxidase/ onto a cellulose triacetate membrane Oxygen electrode ... 

N.F. Almeida and A.K. Mulchandani, A mediated amperometric enzyme electrode using tetrathiafulvalene and L-glutamate oxidase for the determination of L-glutamic acid, Anal. Chim. Acta, 282(2) (1993) 353-361. 

C.-Y. Chen and Y.-C. Su, Amperometric L-glutamate sensor using a novel L-glutamate oxidase from Streptomyces platensis NTU 3304, Anal. Chim. Acta, 243 (1991) 9-15. 

Glutamate Sensors. The glutamate sensors were constructed using graphite rods (Ultracarbon, Bay City, MI), which were polished to a smooth finish and coated with a small amount of redox polymer (0.033 Mmole of polymer-bound ferrocene) dissolved in chloroform. After evaporation of the solvent, a 5 m1 aliquot of glutamate oxidase (Yamasa Shoyu Co., Japan) solution (100 units/ml in pH 7.0 phosphate buffer) was added to the surface and allowed to dry at room temperature. The electrodes were stored under dry conditions at 5°C. 

Figure 15. Typical steady-state current response for a ferrocene-ethylene oxide-siloxane polymer (I) / glutamate oxidase / graphite rod electrode at an applied potential of +350 mV vs. SCE.

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