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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Norepinephrine

  • IUPAC Name: 4-[(1R)-2-amino-1-hydroxyethyl]benzene-1,2-diol
  • Molecular Formula: C8H11NO3
  • CAS Registry Number: 51-41-2
  • InChI: InChI=1S/C8H11NO3/c9-4-8(12)5-1-2-6(10)7(11)3-5/h1-3,8,10-12H,4,9H2
  • InChI Key: SFLSHLFXELFNJZ-QMMMGPOBSA-N

@ ChemSpider@ NIST@ PubChem

Citations 9

"Amperometric Determination Of Sympathomimetic Drugs By Flow Injection Analysis With A Metallic Copper Electrode"
Anal. Chim. Acta 1999 Volume 379, Issue 1-2 Pages 81-88
M. Chicharro, A. Zapardiel, E. Bermejo, J. A. Pérez and L. Hernández

Abstract: The detection and determination of sympathomimetic drugs in flow injection systems with an amperometric method based on a metallic copper wire electrode is described. The copper electrode is shown to give sensitive response toward sympathomimetic drugs, especially for norephedrine in flow injection analysis. The copper electrodes require no pretreatment except polishing before use. Furthermore, the copper working electrode shows stable response in such a system and the relative standard deviation is only 4.6% for 30 consecutive norephedrine injections at a 0.15 mM level. A detection limit of 10^-9 mol (0.15 µg norephedrine) for a sample loop of 0.1 mi was obtained at a fixed potential of +0.6 V (vs. Ag/AgCl) in NaOH 0.1 M and a Bow rate of 2.0 ml/min.
Amperometry Electrode

"Plant Tissue-based Amperometric Electrode For Eliminating Ascorbic Acid Interferences"
Anal. Chim. Acta 1990 Volume 234, Issue 2 Pages 315-320
Joseph Wang, Najih Naser and Mehmet Ozsoz

Abstract: Ground courgette tissue (0.4 g) was mixed into a slurry with graphite powder (0.9 g) and mineral oil (0.7 g). A portion of the paste was packed into one end of a 2 mm i.d. glass tube for voltammetry or into the electrode cavity of a thin-layer detector for flow experiments. The presence of ascorbic acid oxidase in the tissue eliminated interference by ascorbic acid. The electrode was applied in the analysis of dopamine and norepinephrine. Uricase-containing pastes were prepared in the same way and co-immobilized to obtain simultaneous elimination of uric acid interferences. The effects of various experimental variables were studied using pulse voltammetry, chronoamperometry and flow injection amperometry. Compared with enzyme-based ascorbic acid oxidase electrodes, the tissue electrode offers high biocatalytic stability and activity at very low cost.
Voltammetry Electrode Amperometry Interferences Graphite Enzyme Immobilized enzyme Activity Low cost

"Flow Injection Analysis Methods For Determination Of Diffusion Coefficients"
Anal. Chim. Acta 1997 Volume 350, Issue 3 Pages 359-363
Gongwei Zou*, Zhen Liu and Congxiang Wang

Abstract: Two flow injection analyzes (FIA) methods for the determination of diffusion coefficients in a straight single tube FIA system were developed. Based on the analytical solution of the convection-diffusion equation, linear relationships of the logarithmic values of the dispersion coefficient (D) and the half-peak width (W-1/2) with the diffusion coefficient (D-m) were obtained. Experiments were designed to verify these methods. For example, for potassium hexacyanoferrate (III) a D-m value of 0.72 x 10(5) cm(2) s-1 was found versus a literature value of 0.76 x 10(5) cm(2) s-1 (error, 5%). For potassium hexacyanoferrate (II) a D-m value of 0.67 x 10(5) cm(2) s-1 was obtained versus a literature Value of 0.63 x 10(5) cm(2) s-1 (error, 6%). The diffusion coefficients of some important biomedical compounds, such as dopamine, epinephrine, norepinephrine and ascorbic acid, were then determined. The values of 10(5) D-m/cm(2) s-1 are 0.60±0.03, 0.44±0.02, 0.60±0.01 and 0.68±0.06, respectively. 18 References
Straight tube Diffusion coefficients Peak width

"Background Current Subtraction In Voltammetric Detection For Flow Injection Analysis"
Talanta 1984 Volume 31, Issue 5 Pages 387-390
Joseph Wang* and Howard D. Dewald

Abstract: Compensation for background currents due to evolution of H, reduction of O, solvent oxidation or surface processes was made by recording the voltammogram while the sample and carrier solution flowed through the cell and taking the difference as the net response for the sample. The electrochemical detector was that described previously (Anal. Chim. Acta, 1983, 153, 325). Various 3-mm diameter disc working electrodes were used, including mercury-coated vitreous carbon (for measurements in the cathodic region), bare vitreous carbon and carbon paste. A silver - AgCl reference electrode and a carbon-rod auxiliary electrode were used. All measurements were made with a Sargent-Welch model 4001 polarograph. At a flow rate of 0.3 mL min-1, ~15 samples per h could be analyzed. The coefficient of variation for 25 µM-Pb was 0.4% (n = 7); other test analytes included Bi, phenol, chlorpromazine and noradrenaline.
Environmental Electrode Electrode Electrode Voltammetry

"Flow Injection Chemiluminometric Determination Of Epinephrine, Norepinephrine, Dopamine And L-dopa"
Analyst 1993 Volume 118, Issue 6 Pages 627-632
Nikolaos T. Deftereos, Antony C. Calokerinos and Constantinos E. Efstathiou

Abstract: The determination of the cited drugs (I), (II), (III) and (IV) by their chemiluminogenic oxidation with KMNO3 in acidic medium was conducted using a flow manifold with a peristaltic pump and PTFE tubes. The sample was injected into the carrier stream by a 500 µL loop of a low-pressure PTFE injection valve. The effects of flow rate, KMNO3 concentration, acid concentration, emission enhancers, and formaldehyde as an enhancer were investigated. The presence of formaldehyde improved the sensitivity. The calibration graphs were rectilinear from 0.05 to 1.0 µg mL-1 of I and II and 0.1 to 1.0 µg mL-1 of III and IV, respectively. The corresponding detection limits were 0.03, 0.05, 0.03 and 0.04 µg l-1. The necessary chemiluminescent requirement was found to be an electron-donating group on the benzene ring. A method is proposed for the determination of 0.0500-1.00 µg mL-1 of epinephrine and L-dopa and 0.100-1.00 µg mL-1 of norepinephrine and dopamine by their chemiluminogenic oxidation with potassium permanganate in acidic medium, in the presence of formaldehyde, which greatly improves the sensitivity. Flow injection allows the measurement of 80 solutions per hour. The method was also optimized for a continuous-flow system. Comparative results from numerous organic compounds proved the necessity for electron-donating groups on the benzene ring for sensitive chemiluminescent characteristics.
Chemiluminescence

"A Thin-layer Electrochemical Detector Coated With Nafion Film For Liquid Chromatography"
J. Chromatogr. A 1987 Volume 410, Issue 1 Pages 111-120
Huamin Ji and Erkang Wang

Abstract: The selectivity and analytical application of a thin-layer electrochemical detector comprised of glassy carbon electrode coated with Nafion film were investigated. As a result of the ion-exchange characteristics of the Nafion polymer, the selectivity and stability were improved greatly. The coated electrode has a good response only for cations with the same sensitivity as an uncoated (bare) electrode, but not for anions, and the response for neutral molecules is decreased three-fold. The diffusion of electroactive compounds in Nafion film is discussed based on the results of flow injection experiments. The peak current at the coated electrode was independent of the flow-rate of the mobile phase. Electrode poisoning due to protein adsorption was minimized. The use of 30% methanol or 10% acetonitrile in the mobile phase did not affect the performance of the coated electrode. Various analytes having three kinds of charge state, i.e., anionic, cationic and neutral, were tested. Liquid chromatography with electrochemical detection of ascorbic acid, norepinephrine, epinephrine, dopamine and uric acid was demonstrated.
Electrode Diffusion Detector

"Novel Post-column Derivatization Method For The Fluorimetric Determination Of Norepinephrine And Epinephrine"
J. Chromatogr. B 1980 Volume 221, Issue 2 Pages 249-255
Noriyuki Nimura, Kyoko Ishida and Toshio Kinoshita

Abstract: A novel method is described in which catecholamines are converted into fluorescent products by heating in alkaline borate buffer. The method was applied to the determination of norepinephrine and epinephrine after separation by high-performance liquid chromatography using a pellicular, strong cation exchanger. The new system is simpler than the system based on the trihydroxyindole reaction. It is suitable for the measurement of catecholamines in the range 0.25-20 ng. The assay of catecholamines in human urine is also described.
Fluorescence Post-column derivatization

"Flow Injection Spectrophotometric Determination Of Adrenaline And Dopamine With Sodium-hydroxide"
J. Pharm. Biomed. Anal. 1996 Volume 14, Issue 5 Pages 571-577
J. J. Berzas Nevado*, J. M. Lemus Gallego and P. Buitrago Laguna

Abstract: A new, rapid and economical flow injection method for determining adrenaline and dopamine is proposed on the basis of the hydrolysis of these compounds in alkaline medium. The method was optimized by using a spectrophotometer operating at lambda = 390 nm as detector. Calibration graphs were linear up to 2 x 10^-4 M with quantification limits of 2.5 x 10^-6 M and 3.3 x 10^-6 M for dopamine and adrenaline respectively. Flow injection allows the measurement of 130 samples per hour. The method was successfully applied for the determination of catecholamines in pharmaceuticals. A flow injection spectrophotometric method for the determination of adrenaline (I) and dopamine (II) in pharmaceuticals, based on their hydrolysis to colored aminochrome derivatives in alkaline medium, is presented. Pharmaceutical formulations were diluted appropriately with 50 mM acetate buffer of pH 4.8 and a 350 µL portion was injected into a stream of water carrier solution (2 ml/min) heated at 65°C in a flow injection manifold (schematic shown). The sample stream was merged with a reagent stream of 0.4 M NaOH flowing at the same rate and the mixture was pumped through a reactor (2.7 m x 0.5 mm i.d.) and the products were detected at 390 nm in a flow cell. Beer`s law was obeyed up to 200 µM-I and -II and the corresponding detection limits were 0.76 and 0.97 µM. The method was applied to the analysis of three pharmaceutical preparations (listed). Results were in good agreement with labelled values.
Pharmaceutical Spectrophotometry Heated reaction Buffer

"High Performance Liquid Chromatographic Determination Of Total Catecholamines And Metabolites In Human Urine By Application Of The Fluorescence Derivatization Method For Their Free Form"
Anal. Sci. 1993 Volume 9, Issue 4 Pages 537-540
H. NOHTA, H.-K. JEON, M. KAI and Y. OHKURA

Abstract: Urine was hydrolyzed with 1 M HClO4, 30 mM Na2EDTA and 0.1 M reduced glutathione at 100°C for 20 min to determine the total amino-compounds (TAC) and for 50 min to determine the total acidic and alcoholic compounds (TAAC). The internal standard, 30 µM isoproterenol was added prior to hydrolysis for TAC and after for TAAC, which after clarification (described), were separated by HPLC (cf. Anal. Biochem., 1992, 200, 332) and identified by post-column derivatization using periodate oxidation followed by fluorescence detection with meso-1,2-diphenylethylenediamine. Calibration graphs were linear from 10^-3000 pmol of vanillylmandelic acid and 4-hydroxy-3-methoxyphenylethylene glycol (I), and from 0.2-200 pmol of norepinephrine (II), epinephrine, dopamine, normetanephrine, metanephrine, 3-methoxytyramine, 3,4-dihydroxyphenylacetic acid, and homovanillic acid. The corresponding detection limits were 60, 90, 0.3, 0.7, 2, 0.4, 1, 2, 5, and 5 pmol/ml, in urine. The RSD were 4.5 and 5% for I and II, respectively, and 3% for all the others.
Urine Fluorescence HPLC Post-column derivatization