Biomedical subjects

D Dye

Publications and source records attributed to D Dye.

27 records · Page 2Linked to original sources

PubMed1984

High-performance liquid chromatographic method for post-column, in-line derivatization with o-phthalaldehyde and fluorometric detection of phenylpropanolamine in human urine.

A rapid and sensitive method for the analysis of phenylpropanolamine in urine was developed using high-pressure liquid chromatography, post-column, in-line derivatization with o-phthalaldehyde, followed by detection with a fluorometer. Human urine was injected directly into the chromatographic system, and phenylpropanolamine separated in the reversed-phase mode. The practical lower limit of detection was 0.1 microgram/ml of urine. The coefficient of variation from 0.96 to 96 micrograms/ml varied between 2.23 and 0.19%, respectively. The linearity of the calibration graphs is excellent (r = 0.9999) over a concentration range of two orders of magnitude.

Amphetamine↗

PubMed1984

Electron-capture capillary gas chromatographic determination of phenylpropanolamine in human plasma following derivatization with trifluoroacetic anhydride.

A capillary gas chromatographic analysis of phenylpropanolamine in human plasma, following extraction and derivatization with trifluoroacetic anhydride, is presented. Using an electron-capture detector, the method was sensitive enough to quantitate as little as 1 ng of drug/mL of plasma. The coefficient of variation from 5-262 ng/mL varied between 5.6 and 1.6%, respectively. Plasma concentration data following one 25-mg dose of phenylpropanolamine hydrochloride in four healthy volunteers illustrates the suitability of this analytical method for monitoring plasma levels after oral administration of a typical dosage form.

Acetic Anhydrides↗

PubMed1984

Single catalytic site model for the oxidation of ferrocytochrome c by mitochondrial cytochrome c oxidase.

A single catalytic site model is proposed to account for the multiphasic kinetics of oxidation of ferrocytochrome c by cytochrome c oxidase (ferrocytochrome c:oxygen oxidoreductase, EC 1.9.3.1). This model involves nonproductive binding of substrate to sites near the catalytic site on cytochrome c oxidase for cytochrome c, decreasing the binding constant for cytochrome c at the catalytic site. This substrate inhibition results in an increase in the first-order rate constant for the dissociation of the ferricytochrome c-cytochrome c oxidase complex, the rate-limiting step in the steady-state turnover of electrons between cytochrome c and cytochrome c oxidase in the spectrophotometric assay, yielding increases in the initial rate as well as the Michaelis constant--namely, multiple kinetic phases.

Animals↗

PubMed1981

High-pressure liquid chromatographic method with postcolumn, in-line hydrolysis and fluorometric detection for indomethacin in biological fluids.

A rapid and sensitive method for the analysis of indomethacin in plasma and urine was developed using high-pressure liquid chromatography, postcolumn, in-line hydrolysis of indomethacin to a fluorophore, and detection of the fluorophore wih a fluorometer. The lower limit of detection was 1.5 ng/ml of plasma. The coefficient of variation at 30 ng/ml of plasma was 4.5% (n = 5). The nonconjugated metabolites of indomethacin, aspirin, and salicylate were resolved from indomethacin and the internal standard, alpha-methylindomethacin.

Chromatography, Gas↗

PubMed1980