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Journal of Biochemical and Biophysical... Aug 1979The differential mobilities of compounds in an electric field are important analytical criteria and we can use them to bring electrophoretically pure components of a...
The differential mobilities of compounds in an electric field are important analytical criteria and we can use them to bring electrophoretically pure components of a mixture medium on which they are separated. To this end, the compound undergoing reaction are brought into positions on the carrier to assure optimal contact between selected fractions, within a predetermined domain of time and distance. The appearance of a product defines their reactivities, and the product's continued migration on the same carrier can provide the first key to its identity as is demonstrated and discussed. The method is called reaction electrophoresis and it will be of particular use in studies with labile components. It is illustrated here with the coupling reaction of the sodium salt of 1,4-naphthol sulfonic acid and tetrazotized o-dianisidine.
Topics: Azo Compounds; Diazonium Compounds; Electrophoresis, Polyacrylamide Gel; Naphthalenesulfonates; Spectrophotometry, Ultraviolet
PubMed: 552387
DOI: 10.1016/0165-022x(79)90007-1 -
Annals of Clinical Biochemistry Jan 2018Background The enzymatic method of caeruloplasmin measurement is based on copper-dependent oxidase activity. The advantage of the oxidase determination is that it has a...
Background The enzymatic method of caeruloplasmin measurement is based on copper-dependent oxidase activity. The advantage of the oxidase determination is that it has a much lower detection limit compared with immunoassay-based methods. It has found its application in both the diagnosis of Wilson's disease and also in the monitoring of patients' response to treatment. Methods The method previously described in literature was adapted for use on a 96-well plate. Caeruloplasmin oxidase activity results were derived from the equation: caeruloplasmin oxidase activity = (A-A) × 185 U/L. Results Repeatability (intra-batch) imprecision ranged from 6 to 15% and intermediate (inter-batch) imprecision varied from 7 to 16% for caeruloplasmin oxidative activities of 14, 29, 45 and 99 U/L. Between 3 and 92 U/L, the assay appeared linear with a regression coefficient R= 0.9958. The lower limit of quantification was 4 U/L. Samples were stable over a five-week period at 4℃ and for at least four freeze-thaw cycles. There was a statistically significant difference between the areas under ROC curve for copper-to-caeruloplasmin ratios between caeruloplasmin oxidative activity and immunoassay-based methods ( P < 0.0171). The reference interval for caeruloplasmin activity was determined to be 12-166 U/L. Conclusions Using the oxidative assay provides a cost-effective means of estimating caeruloplasmin concentrations. The method is easily adaptable to a 96-well plate format that facilitates high throughput of samples in a busy laboratory. The enzymatic method is more sensitive and specific for differentiating between Wilson's and non-Wilson's when compared with immunoassay-based methods.
Topics: Ceruloplasmin; Dianisidine; Hepatolenticular Degeneration; Humans; Limit of Detection
PubMed: 28166667
DOI: 10.1177/0004563217695350 -
The Journal of Biological Chemistry May 1979Extracts of aerobically grown Escherichia coli B exhibit both catalase and dianisidine peroxidase activities. Polyacrylamide gel electrophoresis demonstrates two...
Extracts of aerobically grown Escherichia coli B exhibit both catalase and dianisidine peroxidase activities. Polyacrylamide gel electrophoresis demonstrates two distinct catalases which have been designated hydroperoxidases I and II (HP-I and HP-II) in order of increasing anodic mobility. HP-I has been purified to essential homogeneity and found to be composed of four subunits of equal size. Its molecular weight is 337,000, and it contains two molecules of protoheme IX per tetramer. Its amino acid composition is unusual, for so large a protein, in lacking half-cystine. HP-I is a very efficient catalase with an activity optimum at pH 7.5, a Km for H2O2 of 3.9 mM, and a turnover number of 9.8 x 10(5) per min. It is also a broad specificity peroxidase capable of acting upon dianisidine, guaiacol, p-phenylenediamine, and pyrogallol. Dianisidine acted as a powerful reversible inhibitor of the catalatic activity of HP-I and as a suicide substrate when HP-I functioned in its peroxidatic mode.
Topics: Amino Acids; Dianisidine; Escherichia coli; Kinetics; Macromolecular Substances; Molecular Weight; Peroxidases; Substrate Specificity
PubMed: 374409
DOI: No ID Found -
Clinical Chemistry Dec 1974
Comparative Study
Topics: Analysis of Variance; Aniline Compounds; Anisoles; Bilirubin; Biphenyl Compounds; Ceruloplasmin; Citrates; Copper; Female; Hemoglobins; Humans; Hydrogen-Ion Concentration; Hyperlipidemias; Immunodiffusion; Indicators and Reagents; Iron; Kinetics; Male; Oxidoreductases; Phenylenediamines; Pregnancy; Spectrophotometry; Spectrophotometry, Ultraviolet; Temperature; Time Factors; Urea; Uric Acid
PubMed: 4214636
DOI: No ID Found -
Clinical Biochemistry Mar 1974
Topics: Aniline Compounds; Biphenyl Compounds; Carcinogens; Chemistry, Clinical; Humans; Laboratories; Toluidines; Urinary Bladder Neoplasms
PubMed: 4825692
DOI: 10.1016/s0009-9120(74)90058-7 -
Report on Carcinogens : Carcinogen... 2002
Topics: Animals; Carcinogens; Dianisidine; Environmental Exposure; Government Regulation; Humans; United States
PubMed: 15323044
DOI: No ID Found -
IARC Monographs on the Evaluation of... 1986
Topics: Animals; Benzidines; Chemical Phenomena; Chemistry; Dianisidine; Mice; Mutagenicity Tests; Rats; Rats, Inbred F344
PubMed: 3465689
DOI: No ID Found -
Report on Carcinogens : Carcinogen... 2004
Topics: Animals; Carcinogenicity Tests; Carcinogens; Coloring Agents; Dianisidine; Environmental Exposure; Female; Guidelines as Topic; Humans; Male; Models, Biological; Rats
PubMed: 21089863
DOI: No ID Found -
Carcinogenesis Apr 1985Prostaglandin H synthase oxidized the carcinogens benzidine and o-dianisidine to their respective quinonediimines. Analysis of the reaction media by u.v./visible...
Prostaglandin H synthase oxidized the carcinogens benzidine and o-dianisidine to their respective quinonediimines. Analysis of the reaction media by u.v./visible spectroscopy and liquid chromatography with electrochemical and radiochemical detection revealed that these quinonediimines can be both conjugated and reduced by glutathione, cysteine and N-acetylcysteine. Analysis of the purified conjugate formed between synthetic benzidinediimine and glutathione by proton magnetic resonance spectroscopy demonstrated the product to be 3-(glutathion-S-yl)-benzidine. This metabolite was also formed during peroxidation of benzidine by prostaglandin H synthase in the presence of excess glutathione. These conjugates may be useful markers of peroxidatic activation of aromatic amines in vivo.
Topics: Amines; Benzidines; Dianisidine; Glutathione; In Vitro Techniques; Magnetic Resonance Spectroscopy; Oxidation-Reduction; Prostaglandin-Endoperoxide Synthases; Spectrophotometry, Ultraviolet; Sulfhydryl Compounds
PubMed: 3921272
DOI: 10.1093/carcin/6.4.579 -
Comptes-rendus Des Travaux Du... 1966
Topics: Biphenyl Compounds; Chemical Phenomena; Chemistry; Hydrogen Peroxide; Hydrogen-Ion Concentration; Peroxidases
PubMed: 5956185
DOI: No ID Found