Quantitative measurement of octopamines and synephrines in urine using capillary column gas chromatography negative ion chemical ionization mass spectrometry

Ibrahim, Kamal E.; Couch, Margaret W.; Williams, Clyde M.; Budd, Mary Beth.; Yost, Richard A.; Midgley, John M.

doi:10.1021/ac00273a037

Cited by 29 publications

(9 citation statements)

References 30 publications

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“…Equation (10) is reduced to a more convenient form in Eqn (1 1) from which a good approximation (tilz == 6 x cm is assumed for all neutrals) of D, for any relatively large (MW> 100 gm mol-') neutral in methane can be obtained. D,( cm2 sec-') = 0.063 ( -;3)3/z(y) (11) For example, with 0.5 Torr methane at 423 O K , D, = 185 cmz sec-'.…”

Section: Rate Coefficients Of Individual Processesmentioning

confidence: 99%

Ionization dynamics within the high pressure electron capture mass spectrometer; the unusual spectra of derivatized polycyclic aromatic amines and perchlorinated unsaturated hydrocarbons

Sears

Campbell

Grimsrud

1987

Biol. Mass Spectrom.

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A kinetic model for chemical events occurring within the high pressure electron capture mass spectrometer (HPECMS) ion source is developed which includes four different pathways by which unconventional negative ions can be produced. These routes to unusual ions include reactions of gas phase free radicals, surfaceassisted reactions, ion-electron and ion-ion recombination reactions, and ion-wall neutralization. The model developed here provides a diagnostic tool useful for the elucidation of unusual HPEC spectra. Such spectra for two environmentally important classes of compounds are explained by use of the model. These compound classes include the trifluoroacetic derivatives of polycyclic aromatic amines, which have been shown to be present in materials derived from liquified coal, and the derivatives of hexachlorocyclopentadiene, which are used as pesticides. It is shown in this study that several processes, in addition to electron capture, can be operative in the typical HPECMS ion source, and that these processes can be used advantageously for the generation of informative and sensitive mass spectral signals.

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Section: Rate Coefficients Of Individual Processesmentioning

confidence: 99%

Ionization dynamics within the high pressure electron capture mass spectrometer; the unusual spectra of derivatized polycyclic aromatic amines and perchlorinated unsaturated hydrocarbons

Sears

Campbell

Grimsrud

1987

Biol. Mass Spectrom.

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“…high; we have measured the concentration of the amine itself in human aqueous humour (Watson et al, 1989), and it is -100 times lower. The occurrence of PHMA in the eye is surprising because this is a metabolite of poctopamine fp-synephrine; we have found that isomeric octopamines and mand p-synephrine are present in many mammalian tissues (Ibrahim et al, 1985;Williams et al, 1987) and in human urine (Ibrahim et al, 1984). So far we have not been able to assign any defined biological action for them (Jordan et al, 1987;Williams et al, 1987).…”

Section: Resultsmentioning

confidence: 97%

“…So far we have not been able to assign any defined biological action for them (Jordan et al, 1987;Williams et al, 1987). These compounds also occur at high concentrations in human urine (Ibrahim et al, 1984). Table 2 shows the concentrations of acidic metabolites of biogenic amines in human vitreous humour.…”

Section: Resultsmentioning

confidence: 99%

Determination of Acidic Metabolites of Biogenic Amines in Human Aqueous Humour by Gas Chromatography‐Negative Ion Chemical Ionisation Mass Spectrometry

Watson

McGhee

Midgley

et al. 1992

Journal of Neurochemistry

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The concentrations of acidic metabolites derived from the biogenic amines o-, m-, and p-tyramines (o-, m-, and p-hydroxyphenylacetic acids), p-octopamine/p-synephrine (p-hydroxymandelic acid), and dopamine (homovanillic acid and 3,4-dihydroxyphenylacetic acid) were measured in human aqueous humour obtained from patients undergoing elective surgery for cataract removal or for trabeculectomy as a treatment for chronic open-angle glaucoma. There were no clear differences in the pattern of metabolism of neurotransmitters between the two groups. An unexpected finding was that the o-tyramine metabolite, o-hydroxyphenylacetic acid, was present in aqueous humour.

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“…Liquid chromatography (LC) is the most widely used method for the determination of HP in plant extracts and composite herbal preparations with Pericarpium Citri Reticulatae as their ingredients [15,16,17,18]. Both gas chromatography (GC) [19] and LC [20,21] have been employed for the determination of SP in herbal drugs and biological samples.…”

Section: Introductionmentioning

confidence: 99%

Determination of hesperidin and synephrine in Pericarpium Citri Reticulatae by capillary electrophoresis with electrochemical detection

et al. 2002

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A method based on capillary electrophoresis with electrochemical detection (CE-ED) has been developed for the determination of hesperidin (HP) and synephrine (SP) in the Chinese traditional herbal drug, Pericarpium Citri Reticulatae, the dried rind of the ripe fruits of Citrus reticulata Blanco (mandarin orange). The effects of some important factors such as the acidity and concentration of running buffer, separation voltage, and detection potential were investigated to determine the optimum conditions. The working electrode was a 300 microm diameter carbon disc electrode positioned opposite the outlet of the capillary. Both analytes could be well separated within 5 min in a 40 cm long capillary at a separation voltage of 12 kV in 50 mmol L(-1) borate buffer (pH 9.0). Excellent linearity was observed for the dependence of peak current on analyte concentration in the range from 2.5 x 10(-6) to 1.0 x 10(-3) mol L(-1) for SP and from 5.0 x 10(-6) to 1.0 x 10(-3) mol L(-1) for HP. The detection limits (S/N=3) for SP and HP were 4.96 x 10(-7) mol L(-1) and 6.54 x 10(-7) mol L(-1), respectively. This method has been successfully applied for the analysis of real samples, with satisfactory results.

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Quantitative measurement of octopamines and synephrines in urine using capillary column gas chromatography negative ion chemical ionization mass spectrometry

Cited by 29 publications

References 30 publications

Ionization dynamics within the high pressure electron capture mass spectrometer; the unusual spectra of derivatized polycyclic aromatic amines and perchlorinated unsaturated hydrocarbons

Ionization dynamics within the high pressure electron capture mass spectrometer; the unusual spectra of derivatized polycyclic aromatic amines and perchlorinated unsaturated hydrocarbons

Determination of Acidic Metabolites of Biogenic Amines in Human Aqueous Humour by Gas Chromatography‐Negative Ion Chemical Ionisation Mass Spectrometry

Determination of hesperidin and synephrine in Pericarpium Citri Reticulatae by capillary electrophoresis with electrochemical detection

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