University of North Florida
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Stuart Chalk, Ph.D.
Department of Chemistry
University of North Florida
Phone: 1-904-620-1938
Fax: 1-904-620-3535
Website: @unf

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Classification: Biological fluid -> bile

Citations 4

"High Performance Liquid Chromatographic Determination Of Clenbuterol And Cimaterol Using Post-column Derivatization"
J. Chromatogr. B 1991 Volume 564, Issue 2 Pages 537-549
Dirk Courtheyn*, Carlo Desaever and Roland Verhe

Abstract: Animal tissues, faeces and feeding-stuffs were extracted with dilute 0.5 M HCl saturated with ethyl acetate; the resulting extracts or liquid samples, e.g., urine, plasma, blood and bile were purified on Chem Elut CE 120 columns and eluted with toluene - CH2Cl2. The eluate was mixed with 0.1 M HCl, ultrasonicated and centrifuged before a portion of the mixture was analyzed by HPLC on a column (15 cm x 4.6 mm) of Nova-Pak C18 (4 µm) with 25 mM sodium dodecyl sulfate and 0.02 M anhydrous acetic acid buffer of pH 3.5 containing 1 M NaOH - acetonitrile (53:47) as mobile phase (1.3 mL min-1). The eluate was derivatized with use of three reagents (details given) before the absorbance was measured at 537 and 493 nm for cimaterol and clenbuterol, respectively. Detection limits for liquid and solid samples were 0.1 ng mL-1 and 0.2 ng g-1, respectively. Results agreed well with those obtained by high performance TLC and GC - MS.
Cimaterol Clenbuterol HPLC Spectrophotometry Buffer Column Detection limit pH Post-column derivatization

"Rapid Detection Of Dihydrocodeine By Thermospray Mass Spectrometry"
J. Chromatogr. B 1998 Volume 718, Issue 1 Pages 55-60
Manabu Yoshida*, Atsushi Akane, Yutaka Okii, Sumitaka Yoshimura, Takuma Tokiyasu and Toshimitsu Watabiki

Abstract: Rapid assay of dihydrocodeine (DHC) by thermospray mass spectrometry is explored. Liquid-liquid extractions of blood, urine and gastric contents were injected into a thermospray mass spectrometer, to which there was no column connected, and DHC was assayed by the flow injection method. The mass spectra of DHC under thermospray ionization and filament-on ionization modes consist of the MH+ ion of mlz 302 alone, which was clearly detected in the samples. Although DHC should be quantitated by gas chromatography-mass spectrometry, this method is applicable for rapid identification of DHC in biological materials.
Dihydrocodeine Mass spectrometry

"Determination Of Bile Acids With Immobilized Enzyme On Gel-like Glass Formed With Silicon Tetraethoxide"
Bunseki Kagaku 1984 Volume 33, Issue 1 Pages 6-11
Karatani, H.;Oka, S.

Abstract: The bile acids were separated on a HPLC column incorporated into a flow injection system (shown in a block diagram) and were determined by means of a post-column reaction with 3α-hydroxysteroid dehydrogenase and NAD+, the NADH formed being monitored by fluorimetric detection at 460 nm (excitation at 350 nm). To increase the efficiency of the enzyme reaction, the enzyme was immobilized on the surface of gel-like glass particles (100 µm diameter) prepared by hydrolysis of silicon tetraethoxide. The calibration graph was rectilinear for 2 to 500 ng of each bile acid, the detection limit was 1 ng, and the coefficient of variation was <5% even for the lowest levels of bile acid. There was no degradation of the enzyme even after >300 runs at the 500 ng level of bile acid. A chromatogram, showing clearly separated and well-defined peaks for cholic acid and ursodeoxy-, chenodeoxy-, deoxy- and litho-cholic acids, is reproduced.
Acids, bile HPLC Fluorescence Immobilized enzyme Glass Post-column derivatization

"Determination Of Bile Acid Sulfates With Use Of An Immobilized-enzyme Reactor Based On Flow Injection Chemiluminescence"
Bunseki Kagaku 1997 Volume 46, Issue 5 Pages 357-365
Gao, X.F.;Ji, H.S.;Ikebukuro, K.;Baba, S.;Karube, I.;Li, Y.S.

Abstract: Sample (20 µL) is injected into a carrier stream (0.6 ml/min) of 5 µM-1-methoxyphenazinium methosulfate/50 µM-NAD+ and passes through a reactor (construction illustrated) that incorporates both bile acid sulfate sulfatase (cf. Tazuke et al., Biosci., Biotechnol., Biochem., 1992, 56, 1584) and 3 (or 17) β-hydroxysteroid dehydrogenase immobilized on Reacti-gel. The resulting NADH reduces O2 in the carrier stream to oxide ion and H2O2, which react with a stream (0.6 ml/min) of 40 µM-luminol containing 10 ppm of peroxidase. The resulting chemiluminescence intensity varies linearly for 0.1-12 µM-glycolithocholic acid 3-sulfate. The sampling rate is 30 per h, and RSD were Tolerance limits towards other species are tabulated; the lowest are towards uric acid, creatinine, Ca2+ and Mg2+. Clinical application to urine and blood is envisaged.
Sulfates Chemiluminescence Reactor Immobilized enzyme Interferences