Rate constants for reactions of horseradish peroxidase compounds I and II with 4-substituted arylboronic acids

Sun, Weimei; Ji, Xiaoling; Kricka, Larry J.; Dunford, H. Brian

doi:10.1139/v94-274

Cited by 11 publications

(4 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Figure 3 contrast the results obtained at pH 8.5 and 10.5. These results are consistent with the literature observation of a broad optimum at about pH 8.6 [36].…”

Section: Optimization Of Reagentssupporting

confidence: 94%

Chemiluminescence detection in integrated post‐separation reactors for microchip‐based capillary electrophoresis and affinity electrophoresis

1998

Electrophoresis

123

View full text Add to dashboard Cite

Chemiluminescence (CL) detection based on the horseradish peroxidase (HRP) catalyzed reaction of luminol with peroxide was investigated as a post-separation detection scheme for microchip-based capillary electrophoresis. An integrated injector, separator and post-separation reactor was fabricated on planar glass wafers. The fluorescein conjugate of HRP (HRP-F1) was used as a sample for optimization of the CL detector response. In devices etched 10 microm deep, with an aluminum mirror integrated onto the backside of the detection zone to enhance collection efficiency, the detection limit, estimated at 3 standard deviations (SD) above background noise, for 1 nL injected sample plugs was 35 nM in HRP-F1. In devices etched 40 microm deep, 8 nL plugs gave a detection limit of 7 nM. Separation and CL detection of the products of an immunological reaction of a F(ab')2 fragment of the HRP conjugate of goat anti-mouse immunoglobulin G (IgG) with mouse IgG was performed on-chip. A linear calibration curve was obtained for the decrease in peak height of the HRP conjugate (53 microg/mL) with increasing mouse IgG (0-60 microg/mL). When microperoxidase was used as an internal standard, the R2 value of a linear least-squares fit was 0.9867, and the relative errors in the slope and intercept were +/- 5.8 and +/- 1.3 %, respectively.

show abstract

“…Figure 3 contrast the results obtained at pH 8.5 and 10.5. These results are consistent with the literature observation of a broad optimum at about pH 8.6 [36].…”

Section: Optimization Of Reagentssupporting

confidence: 94%

Chemiluminescence detection in integrated post‐separation reactors for microchip‐based capillary electrophoresis and affinity electrophoresis

1998

Electrophoresis

123

View full text Add to dashboard Cite

show abstract

“…2 ‘ ‘ ,5 ‘ ‘ -Bis(methoxymethyl)-[1,4 ‘ ;1 ‘ ,1 ‘ ‘ ;4 ‘ ‘ ,1 ‘ ‘‘ ;4 ‘ ‘‘ ,1 ‘ ‘‘ ‘ ]quinquephenyl (13a). A mixture of 6 (3.24 g, 10 mmol), biphenylboronic acid (3.92 g, 30 mmol), Pd(PPh 3 ) 4 (0.577 g, 5% mmol), toluene (30 mL), and aqueous 2 M K 2 CO 3 (40 mL) was heated at reflux for 24 h under nitrogen. It was cooled, diluted with water, and extracted with ether.…”

Section: Methodsmentioning

confidence: 99%

Effect of Transannular π−π Interaction on Emission Spectral Shift and Fluorescence Quenching in Dithia[3.3]paracyclophane−Fluorene Copolymers

Wang

Sun

et al. 2006

Macromolecules

View full text Add to dashboard Cite

A series of dithia[3.3]paracyclophane−fluorene copolymers 1a − c and 3 − 5 were synthesized by a palladium-catalyzed reaction between 9,9-di-n-hexylfluorene-2,7-bis(trimethylene boronate) and the corresponding dithiacyclophane precursors. The transannular π−π interaction in the dithiaparacyclophane modified the electronic and optical properties of the copolymers significantly, resulting in emission red shifts relative to a reference polymer 2. The observed shift in 1a and 5 was accompanied by enhanced photoluminescence (PL) efficiency, whereas that in 1b, 1c, 3, and 4 experienced a significant to nearly complete fluorescence quenching. The quenching effect is likely to involve an electron-transfer process and could be correlated qualitatively to the reduction potential of the “external” aromatic moiety in the cyclophane unit.

show abstract

“…Peroxidase from horseradish (EC 1.11.1.7; donor, hydrogen peroxide oxidoreductase) is a heme peroxidase that is able to catalyze the oxidation of a wide range of compounds, including phenols and amines (Dunford & Adeniran, 1986;Job & Dunford, 1976), phenylboronic acids (Sun et al, 1994), phenothiazines (Kelder et al, 1994), indoleacetic acids (Kobayashi et al, 1984;Ricard & Job, 1974), etc. In general, the catalytic cycle is described by the usual paradigm for heme peroxidases, in which the native (ferric) enzyme (HRP) 1 receives two oxidizing equivalents from hydrogen peroxide to form compound I (HRP-I), which in turn oxidizes the substrates by a sequence of two electron-transfer steps.…”

mentioning

confidence: 99%

Rates of Reaction of Indoleacetic Acids with Horseradish Peroxidase Compound I and Their Dependence on the Redox Potentials

et al. 1996

View full text Add to dashboard Cite

The rates of reaction of seven indole-3-acetic acid derivatives with horseradish peroxidase compound 1 at pH 5 were measured by stopped flow, and the reduction potentials and pKa of their radical cations were determined by pulse radiolysis. Reasonable correlation of these properties with Hammett substituent parameters was found, but not with Brown-Okamoto (theta +) parameters. The rates of reaction with compound I correlate well with the reduction potentials under the same conditions, with rates of reaction that increase by ca. 2.5 orders of magnitude with a 100 mV decrease in the reduction potential. This relationship is in agreement with that previously estimated for the reaction of compound I with phenols and anilines, suggesting that the rate of reaction depends solely on the reduction potential of the substrate radical, even for compounds of dissimilar structure.

show abstract

Rate constants for reactions of horseradish peroxidase compounds I and II with 4-substituted arylboronic acids

Cited by 11 publications

References 16 publications

Chemiluminescence detection in integrated post‐separation reactors for microchip‐based capillary electrophoresis and affinity electrophoresis

Chemiluminescence detection in integrated post‐separation reactors for microchip‐based capillary electrophoresis and affinity electrophoresis

Effect of Transannular π−π Interaction on Emission Spectral Shift and Fluorescence Quenching in Dithia[3.3]paracyclophane−Fluorene Copolymers

Rates of Reaction of Indoleacetic Acids with Horseradish Peroxidase Compound I and Their Dependence on the Redox Potentials

Contact Info

Product

Resources

About