An enzyme glucose microsensor using a glucose oxidase-immobilized porous carbon/Teflon composite microelectrode was developed. The microsensor was fabricated by etching a platinum microelectrode (platinum, radius of 25 and 50 micrometers) in hot aqua regia to create a cavity at the tip and then packing a porous carbon/Teflon composite, which was made from acetylene black and Teflon emulsion, in...

Nitroalkanes have been found to be general reductive substrates for D-amino acid oxidase, glucose oxidase and L-amino acid oxidase. These enzymes show different specificities for the structure of the nitroalkane substrate. The stoichiometry of the D-amino acid oxidase reaction is straightforward, consisting of the production of one mole each of aldehyde, nitrite and hydrogen peroxide for each m...

It has been reported (1) that epinephrine, norepinephrine, and serotonin stimulate the oxidation of the first but not the sixth carbon atoms of glucose by beef anterior pituitary slices and rat cerebral cortical fragments. It is shown here that this effect on glucose oxidation is also exerted by other amines which are substrates of monoamine oxidase and that inhibitors of monoamine oxidase bloc...

A micro glucose sensor consisting of an interdigitated array gold microelectrode was developed. The interdigitated array structure, which has 10 microns band width and 10 microns band gap, was fabricated in a small region (2.5 x 5 mm2) on a quartz substrate. Glucose oxidase was chemically fixed onto the electrode surface through self-assembled monolayer of 11-mercaptoundecanoic acid; ferrocenea...

introduction: many of the diseases of adulthood are originated from the intrauterine conditions during fetal life. because of the importance of thyroid hormones in growth and development of the fetus, the effects of maternal hypothyroidism on carbohydrate metabolism in adulthood was investigated. methods: pregnant rats were divided into the fetal hypothyroidism (fh) and the control (c) groups. ...

Surface modification is an important step in developing nanoscale biosensors. The uniform and stable surface structure by forming self-assembled monolayers (SAM) makes it suitable for the development of biosensors. We have studied several surface modification methods on a gold electrode to covalently immobilize the glucose oxidase. The methods with SAM formation were more efficient for immobili...

1. The spectrophotometric and steady-state kinetic properties of glucose oxidase (EC 1.1.3.4, from Aspergillus niger) that is covalently linked to porous glass beads have been examined. These properties have been compared with those of soluble glucose oxidase, for which the kinetic mechanism at pH5.5 and 25°C has been established previously by a combination of conventional and rapid-reaction te...

We report an analytical system in which glucose oxidase immobilized on controlled-pore glass is used. The immobilized glucose oxidase was packed in a column that was part of a continuous-flow system. Oxygen depletion of the buffer was measured with a Clark-type electrode, and the resulting data were stored on tape and then evaluated with a PDP-12 computer. The relative advantages of several mea...

Botrytis cinerea is the causal agent of grey mould disease and a non-host necrotrophic pathogen of maritime pine (Pinus pinaster). Recent evidence suggests that pathogen challenge can alter carbon uptake in plant cells; however, little is known on how elicitor-derived signalling pathways control sugar transport activity. P. pinaster suspended cells are able to absorb D-[14C]glucose with high af...

Glucose oxidase (GO) activity is generally restricted to glucose and is susceptible to inactivation by H2O2. By comparison, the Y300A variant of gluco-oligosaccharide oxidase (GOOX) from Sarocladium strictum showed broader substrate range and higher H2O2 stability. Specifically, Y300A exhibited up to 40 times higher activity on all tested sugars except glucose, compared to GO. Moreover, fusion ...