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
Email: schalk@unf.edu
Website: @unf

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Catecholamine, derivatives

  • CAS Registry Number: NA

@ ChemSpider@ NIST@ PubChem

Citations 8

"Spectrophotometric Determination Of Catecholamines With Metaperiodate By Flow Injection Analysis"
Anal. Chim. Acta 1995 Volume 300, Issue 1-3 Pages 293-297
J. J. Berzas Nevado*, J. M. Lemus Gallego and P. Buitrago Laguna

Abstract: A solution (200 µL) of adrenaline or isoprenaline was injected into a 3 ml/min stream of 0.1% NaIO4 carrier, passed through a 4.3 m-long reactor and mixed with 0.05 M acetic acid/acetate buffer of pH 4.8 also flowing at 3 ml/min. The absorbance was monitored at 491 nm. The calibration graph was linear in the range 5 µM-1 mM, with a working range of 20 µM-0.2 mM. The RSD was 0.5% (n = 10) and the throughput was 120 samples/h. The method was applied to the analysis of pharmaceutical preparations. Powders were dissolved in 0.02 M buffer and liquids were diluted with the buffer prior to injection. The concentrations of the catecholamines were determined from calibration graphs or by the standard additions method.
Pharmaceutical Spectrophotometry Standard additions calibration

"A Study Of Irreversible Electrode Processes Under Steady-state Flowing Solution Conditions With A Microelectrode Based Scanning Electrochemical Detector"
Anal. Chim. Acta 1996 Volume 324, Issue 1 Pages 1-11
Russell J. Taita, Barrie C. Finnina, Barry L. Reeda and Alan M. Bond*, b,*

Abstract: The irreversible oxidation of L-tyrosine and a series of catecholamines at a microelectrode was studied in flowing systems, viz. FIA systems and reversed-phase HPLC. The measurements were carried out with a thin-layer detection cell equipped with either a C fiber (4 µm radius) or a Pt (5 µm radius) disc working electrode, a stainless-steel auxiliary electrode and a Ag/AgCl (3 M KCl) reference electrode. The voltammograms were recorded at a fast potential scan rate (1-2 V/s) and with the mobile phase at 1 ml/min in order to achieve steady-state or near steady-state conditions. Under these conditions the responses were relatively insensitive to kinetic parameters. The 3D chromatovoltammograms of L-tyrosine and the catecholamines are presented and discussed.
HPLC Voltammetry Electrode

"Selective Kinetic Method Based On Detecting The Intermediate Product In Successive Reactions"
Anal. Chim. Acta 1996 Volume 325, Issue 1-2 Pages 105-109
Xinguo Wu, Ruxiu Cai*, Zhixin Lin and Jieke Cheng

Abstract: A kinetic method for the analysis of binary mixtures was developed based on: (i) detecting an intermediate reaction product which has a peak-shaped kinetic curve; and (ii) selecting two measurement times (t1 and t2) where the interfering species produces two equal signal intensities and the analyte produces different signal intensities. The method was applied to the determination of epinephrine in the presence of norepinephrine using a flow injection stopped-flow technique and utilizing the alkaline oxidation of epinephrine by dissolved O2 to the indole intermediate. A sample stream was merged with a 1 M NaOH stream and the mixture was propelled to the detection cell which was maintained at 30°C. The flow was stopped and the fluorescence intensity at 510 nm (excitation at 410 nm) was monitored. The difference in the fluorescence intensities at t1 = 2 min and t2 = 8 min was used to calculate the epinephrine concentration. The calibration graph was linear for 0.2-8 µM, the detection limit was 0.04 µM and the RSD (n = 11) for 1 µM-epinephrine was 4.6%. The method was tested by analyzing synthetic mixtures containing epinephrine, dopamine, dopa and norepinephrine.
Fluorescence Interferences Kinetic Stopped-flow

"Flow Injection Analysis Of Phenolic Compounds With Carbon Paste Electrodes Modified With Tyrosinase Purchased From Different Companies"
Anal. Lett. 1996 Volume 29, Issue 7 Pages 1055-1068
Lindgren, A.;Ruzgas, T.;Emmeus, J.;Csoregi, E.;Gorton, L.;Marko Varga, G.

Abstract: Tyrosinase-modified C paste electrodes were prepared by several methods: (i) direct mixing of tyrosinase powder with graphite and oil vs. adsorption of tyrosinase from solution on to graphite powder, drying and mixing with oil; (ii) preparation of tyrosinase-modified paste doped with mediator vs. mediatorless; and (iii) preparation of C paste using porous graphite vs. non-porous vitreous C powder. Each design was evaluated for nine phenolic compounds including six substituted catechols. Samples (220 µL) were aspirated into a flow injection system (schematic given) and injected into a 0.1 M phosphate buffer of pH 6 carrier stream (0.8 ml/min). After mixing, detection was at tyrosinase-modified paste electrodes inserted into a flow-through wall-jet electrochemical cell, with Pt and Ag/AgCl as counter and reference electrodes, respectively, operated at -0.05 V vs. AgCl. The tyrosinase-modified C paste electrode response was limited by the rate of the enzymatic reaction; higher responses were obtained for direct mixing of the enzyme powder on to the paste and mediator-doped pastes exhibited a higher response for some phenols.

"NMR-studies Of The Interaction Of Catechol And Ascorbic-acid With The Crown-ether"
Anal. Lett. 1996 Volume 29, Issue 8 Pages 1309-1318
Lunsford, S.K.;Striley, C.A.;Ma, Y.L.;Zimmer, H.;Kreishman, G.;Mark, H.B.

Abstract: Various crown ethers have been electropolymerized onto a platinum electrode for the determination of catechol and catecholamines by static potentiometry and potentiometric-flow injection analysis(FIA). The response mechanism of this modified electrode was investigated by scanning electron microscopy (SEM), electron dispersive X-ray analysis (EDAX), and electron spectroscopy for chemical analysis(ESCA). However, these studies were not conclusive with respect to possible mechanisms, and, therefore, nuclear magnetic resonance (NMR) studies were carried out on similar soluble crown ethers to determine the mode of interaction. As the crown ether resonances were shifted to higher fields by the added catechol in D2O but not d(6)-DMSO, it is postulated that the crown ether and catechol associate via interactions between hydrophobic surfaces. Hydrophilic ascorbic acid showed no NMR shifts which is consistent with its lack of potentiometric response. The EDAX and ESCA results indicated that then was also an interaction of catechol with the crown itself but the NMR shows that this interaction is a secondary effect in the overall electrode response. Several crown ethers were electropolymerized on to Pt electrodes for the determination of catechol and catecholamines by static potentiometry and flow injection potentiometry. The response mechanism of the resulting electrodes was investigated by scanning electron microscopy, electron dispersive X-ray analysis and electron spectroscopy for chemical analysis. These results were inconclusive and so 400 MHz 1H NMR Spectra were recorded with use of a Bruker AMX-400 MHz multinuclear spectrometer. NMR data indicated that crown ether aromatic rings and catechol rings were stacking on top of each other. Hydrophobic interaction seemed to be the major form of interaction which was confirmed by NMR studies in DMSO.
Electrode Nuclear magnetic resonance Potentiometry Crown ether

"The Application Of Various Immobilized Crown Ether Platinum-modified Electrodes As Potentiometric And Amperometric Detectors For Flow Injection Analyses Of Catechol And Catecholamines"
Electroanalysis 1995 Volume 7, Issue 5 Pages 420-424
Suzanne K. Lunstord, Yi-Long Ma, Ahmed Galal, Cynthia Striley, Hans Zimmer, Harry B. Mark Jr.

Abstract: The crown ethers were polymerized onto a 2 mm diameter Pt disc electrode. The monomer solution comprised 0.025 M crown ether and 0.20 M tetrabutylammoniumtetrafluoriborate as supporting electrolyte in acetonitrile. Amperometric measurements were performed with a BAS model MF-1021 flow cell. Static potentiometric and potentiometric FIA measurements were performed with the polymer-modified electrode PTFE block incorporated into a standard BAS thin-layer flow cell with a Ag/AgCl electrode as second electrode. Measurements were performed with an Orion model 601A ionanalyzer. The potentiometric FIA response of all the crown ethers was linear over the range 10 mM to 10 µM. The lowest detection limits were 0.5 µmM for the potentiometric FIA with minimum interference from ascorbic acid, uric acid and acetaminophen. Detection limits for amperometric FIA was 5 µmM but there was significant interference from ascorbic acid, uric acid and acetaminophen.
Amperometry Electrode Electrode Potentiometry Crown ether Complexation Interferences

"Simultaneous Determination Of Catecholamine-related Compounds By High Performance Liquid Chromatography With Post-column Chemical Oxidation Followed By A Fluorescence Reaction"
Anal. Sci. 1991 Volume 7, Issue 2 Pages 257-262
H. -K. JEON, H. NOHTA, H. NAGAOKA and Y. OHKURA

Abstract: Thirteen such compounds (three catecholamines, one precursor and nine metabolites), together with isoprenaline and 3-(3,4-dihydroxyphenyl)propionic acid, were separated on a TSK-gel ODS-80TM column (25 cm x 4.6 mm) with methanol - 0.4 mM Na octane-1-sulfonate in 30 mM citrate buffer (7:93) as mobile phase (0.8 mL min-1). The separated components were oxidized to the corresponding o-quinones by treatment with 10 mM NaIO4 - 3 mM K3Fe(CN)6, and these were converted into fluroescent derivatives by reaction with 30 mM meso-1,2-diphenylethylenediamine in aqueous 70% ethanol solution containing 0.13 M Na methoxide. The fluorescence intensity was monitored continuously at 480 nm (excitation at 350 nm). Detection limits ranged from 14 fmol for adrenaline to 570 fmol for (4-hydroxy-3-methoxyphenyl)ethanediol, and coefficient of variation were ~3.1% (n = 10).
HPLC Fluorescence Buffer Column Post-column derivatization

"Chemiluminescence Analysis Of Biological Substances Using Lucigenin (bis-N-methylacridine)"
Biol. Pharm. Bull. 1984 Volume 7, Issue 1 Pages S8-S8
MAEDA MASAKO, TSUJI AKIO

Abstract: Two flow injection methods are described, based on the chemiluminescence reaction of lucigenin with oxidizing or reducing agents in alkaline solution In the first method, steroid sulfates were determined after extraction into an organic solvent through a membrane separator as an ion pair with lucigenin. The extracted ion pair was then mixed with alkaline H2O2 solution, and the resulting chemiluminescence intensity was determined. Response was rectilinear in the range 3 to 30 pmol. Steroid glucuronides, bile acid 3-O-sulfates and bile acids were also detectable by this method, although with less favourable detection limits. In the second reaction, the chemiluminescence reactions of lucigenin with various biological substances were studied with and without NaIO4. Rectilinear responses were obtained for glucose and phenacyl alcohol in the ranges 70 to 700 pmol and 1.8 to 73 pmol, respectively.
Chemiluminescence Sample preparation Extraction