Horseradish peroxidase hydrogen peroxide determination

S-cyclodextrin condensation, 630 horseradish peroxidase mimic, 628-9, 630 hydrogen peroxide determination, 639 hydroperoxide determination, 681, 708 Hemoglobin see Haemoglobin Henry s law constants... 

Razola SS, Aktas E, Vire JG et al. Reagentless enzyme elearode based on phenothiazine mediation of horseradish peroxidase for subnanomolar hydrogen peroxide determination. Analyst 1999 125 79-85. 

S. S. Razola, E. Aktas, J.-C. Vire, J.-M. Kauffmann, Reagentless Enzyme Electrode Based on Phenothiazine Mediation of Horseradish Peroxidase for Subnanomolar Hydrogen Peroxide Determination. Analyst, 125 (2000) 79-85. 

J.L. Tang, B.Q. Wang, Z.Y. Wu, X.J. Han, S.J. Dong, and E.K. Wang, Lipid membrane immobilized horseradish peroxidase biosensor for amperometric determination of hydrogen peroxide. Biosens. Bioelectron. 18, 867-872 (2003). 

HTAC cationic micelles also markedly enhance the CL intensity of fluorescein (FL) in the oxidation of hydrogen peroxide catalyzed by horseradish peroxidase (HRP) [39], However, no CL enhancement was observed when anionic micelles of sodium dodecyl sulphate (SDS) or nonionic micelles of polyoxyethylene (23) dodecanol (Brij-35) were used (Fig. 9). CL enhancement is attributed to the electrostatic interaction of the anionic fluorescein with the HTAC micelles. The local concentration of fluorescein on the surface of the micelle increases the efficiency of the energy transferred from the singlet oxygen (which is produced in the peroxidation catalyzed by the HRP) to fluorescein. This chemiluminescent enhancement was applied to the determination of traces of hydrogen peroxide. The detection limit was three times smaller than that obtained in aqueous solution. 

An experimental set-up such as that depicted in Fig. 5.12.C was also used by Nieman s group for the determination of free and total cholesterol in serum [37]. A solution of the enzyme (cholesterol oxidase) at pH 7 was forced through a microporous membrane. The pH gradient across the membrane (from 7 to 9) facilitated the enzymatic degradation of the analyte and subsequent diffusion of the hydrogen peroxide formed to the PMT in the reagent/sample stream in order to react with luminol in the presence of horseradish peroxidase as the catalyst at pH 9 —the copper chelate commonly used as catalyst for this purpose requires pH 11. The system per-... 

Materials. Horseradish peroxidase (type II, 200 purpurogallin units per mg protein) and non-porous glass beads (75-150 1 diameter) were obtained from Sigma Chemical Co. (St. Louis, MO). p-Cresol, hydrogen peroxide (as a 30% solution in water) and dioxane (HPLC grade) were obtained from Aldrich Chemical Co. (Milwaukee, WI). The actual H2O2 content was determined spectrophotometrically at 240 nm. 

A similar approach was used for the detection of monosaccharides [56] pyranose oxidase delivered a suitable oxidase-based sensor with the hydrogen peroxide being determined again via the direct electron transfer from the carbon paste electrode to the enzyme horseradish peroxidase. In aU bi-enz5mie systems, both the enzymes were entrapped within the carbon paste. These electrodes were used as detectors in a liquid chromatography system allowing the simultaneous determination not only of several carbohydrates but also of ethanol within approximately 20 min. Ethanol production and carbohydrate consumption were monitored on-line during a fermentation of P. stipitis for 16 h (see also Section 11.2.3). 

The direct anodic oxidation of cytochrome c at a bipyridyl-modified electrode has already been incorporated in enzyme electrodes for lactate, carbon monoxide, and hydrogen peroxide. Here, cytochrome c is reduced by cytochrome b2, CO oxidoreductase, or horseradish peroxidase and anodically reoxidized. Cytochrome c has also been applied to couple mitochondria and chloroplasts to redox electrodes (Albery et al. 1987). Although no practically applicable sensor has been constructed as yet, this principle offers a new avenue to the determination of inhibitors of photosynthesis or respiration (Cardosi and Turner, 1987). 

Aizawa (1982) patented a lectin electrode based on the binding of horseradish peroxidase via its carbohydrate groups to con A immobilized on a hydrogen peroxide sensitive probe. The bound enzyme activity was determined from the H2O2 consumption catalyzed by HRP. 

Nozfiki O, Kawamoto H. Determination of hydrogen peroxide by micro-flow injection-horseradish peroxidase catalyzed "imidazole chemiluminescence". In Stanley PE, Kricka LJ. eds. Bioluminescence Chemiluminescence- Progress Current Applications. Singapore World Scientific, 2002 335-8. 

Nozaki O, Kawamoto H. Reactivation of horseradish peroxidase with imiaazole for continuous determination of hydrogen peroxide using a micro-flow injection -chemiluminescence detection system. Luminescence 2003 18 203-6. 

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