381721

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Mass spectrometric identification and quantification of 5-methoxytryptophol in quail retina.

C W Tsang et al.

Biochemical and biophysical research communications, 165(3), 1331-1336 (1989-12-29)

The occurrence of 5-methoxytryptophol (5-MTL) in the quail retina was investigated by capillary column gas chromatography/mass spectrometry/selected ion monitoring using a deuterated internal standard. Based on ion intensity ratios in the mass spectra of pentafluoropropionyl and heptafluorobutyryl derivatives of 5-MTL

New fluoro intermediates for herbicidal sulfonylureas.

Hamprecht G, et al.

Pestic. Sci., 55(5), 566-570 (1999)

Atmospheric pressure deposition of fluorine-doped SnO2 thin films from organotin fluorocarboxylate precursors.

Mahon MF, et al.

Applied Organometallic Chemistry, 19(5), 658-671 (2005)

Determination of hair polyamines as N-ethoxycarbonyl-N-pentafluoropropionyl derivatives by gas chromatography-mass spectrometry.

M H Choi et al.

Journal of chromatography. A, 897(1-2), 295-305 (2000-12-29)

An efficient method is described for the simultaneous determination of hair polyamines, such as 1,3-diaminopropane, putrescine, cadaverine, spermidine and spermine, by gas chromatography-mass spectrometry (GC-MS) with the selected ion-monitoring (SIM) mode. The method is based on the extractive two-phase ethoxycarbonyl

Measurement of plasma testosterone by gas chromatography-negative-ion mass spectrometry using pentafluoropropionic derivatives.

C Legrand et al.

Journal of chromatography. B, Biomedical applications, 663(2), 187-192 (1995-01-20)

Plasma testosterone was measured by gas chromatography-negative-ion chemical ionisation mass spectrometry (GC-MS). The testosterone was extracted from plasma using home-made Extrelut columns and diethyl ether elution. It was quantified as the pentafluoropropionate (PFP) derivative by selected-ion monitoring at m/z 560

Rational method development strategies on a fluorinated liquid chromatography stationary phase: mobile phase ion concentration and temperature effects on the separation of ephedrine alkaloids.

David S Bell et al.

Journal of chromatography. A, 1095(1-2), 113-118 (2005-11-09)

Fluorinated, silica-based stationary phases are becoming increasingly popular alternatives to traditional alkyl phases owing to their differential selectivity and retention for a variety of analyte classes. In this report, the ion-exchange mechanisms characteristic of a fluorinated phase are exploited to

Determination of amines as pentafluoropropionic acid anhydride derivatives in biological samples using liquid chromatography and tandem mass spectrometry.

Asa Marand et al.

The Analyst, 129(6), 522-528 (2004-05-21)

Determination of amines in biological samples as markers of exposure to the amines or the corresponding isocyanates is an important tool for industrial exposure assessment. In this study, a liquid chromatography and tandem mass spectrometry (LC-MS/MS) method for determination of

Mass spectral investigations on trichothecene mycotoxins. III. Synthesis, characterization and applications of pentafluoropropionyl and trifluoroacetyl esters of simple trichothecenes.

T Krishnamurthy et al.

Journal of chromatography, 355(1), 253-264 (1986-03-14)

The pentafluoropropionyl, (PFP) and trifluoroacetyl (TFA) esters of several naturally occurring and synthetically modified simple trichothecenes were synthesized in nanogram amounts and characterized. Optimum conditions for the gas chromatographic (GC) separation of these derivatives and their analysis by negative ion

Analysis of anatoxin-a in freshwaters by automated on-line derivatization-liquid chromatography-electrospray mass spectrometry.

M Takino et al.

Journal of chromatography. A, 862(2), 191-197 (1999-12-22)

Anatoxin-a is a toxin produced from cyanobacterial blooms in freshwaters. In order to determine trace anatoxin-a in freshwaters, an automated on-line derivatization procedure with fluorenyl methylchloroformate using liquid chromatography-electrospray ionization mass spectrometry was developed. Anatoxin-a was extracted using solid-phase extraction

One-dimensional coordination polymers incorporating silver(I) perfluorocarboxylate cuboctahedral clusters and the bis(methylthio)methane ligand.

Mohamed Osman Awaleh et al.

Inorganic chemistry, 46(8), 3185-3191 (2007-03-17)

Two topologically comparable complexes, [Ag6(CF3CO2)3(L1-Me)3(SCH3)3]infinity (1) and [Ag6(CF3CF2CO2)3(L1-Me)2(SCH3)3(H2O)]infinity (2), were prepared and characterized by single-crystal diffractometry. The structures consist of Ag12S6 clusters linked by bis(methylthio)methane ligands, L1-Me, thus forming 1D coordination polymers. The 12 Ag atoms of the cluster are

Passage of MHPG from plasma to CSF in a non-human primate.

K F Faull et al.

Journal of neuroscience research, 27(4), 533-540 (1990-12-01)

In experimental protocols with humans and non-human primates, cerebrospinal fluid (CSF) concentrations of 3-methoxy-4-hydroxyphenylethylene glycol (MHPG), the predominant end-product of norepinephrine metabolism in the mammalian central nervous system (CNS), have been widely used as an index of the rate of

Determination of toluenediamine isomers by capillary gas chromatography and chemical ionization mass spectrometry with special reference to the biological monitoring of 2,4- and 2,6-toluene diisocyanate.

G Skarping et al.

Journal of chromatography. A, 663(2), 199-210 (1994-03-11)

The determination of 2,3-, 3,4-, 2,6-, 2,4- and 2,5-toluenediamine (TDA) in hydrolysed human urine and blood plasma was studied by GC-MS. The TDA isomers as their perfluoro-fatty acid anhydride derivatives were investigated. Chemical ionization with ammonia and isobutane as reagent

Comparison of liquid chromatographic methods with direct detection for the analysis of gentamicin.

Vicky Manyanga et al.

Journal of pharmaceutical and biomedical analysis, 45(2), 257-262 (2007-08-21)

Several liquid chromatographic (LC) methods have been described for the analysis of gentamicin. LC combined with pulsed electrochemical detection (LC-PED) or evaporative light scattering detection (LC-ELSD) was found to be the most suitable technique. A first method, previously developed by

Context-dependent effects on the hydrophilicity/hydrophobicity of side-chains during reversed-phase high-performance liquid chromatography: Implications for prediction of peptide retention behaviour.

C T Mant et al.

Journal of chromatography. A, 1125(2), 211-219 (2006-07-04)

The present study set out to investigate whether observed relative hydrophilicity/hydrophobicity values of positively charged side-chains (with Lys and Arg as representative side-chains) or hydrophobic side-chains (with Ile as the representative side-chain) were context-dependent, i.e., did such measured values vary

C-terminal sequencing of protein. A novel partial acid hydrolysis and analysis by mass spectrometry.

A Tsugita et al.

European journal of biochemistry, 206(3), 691-696 (1992-06-15)

Peptides or proteins were hydrolyzed by vapors of 90% pentafluoropropionic acid or heptafluorobutyric acid at 90 degrees C for various time periods. The hydrolyzate mixtures analyzed by both fast-atom-bombardment and electrospray ionization mass spectrometry showed a series of C-terminal successive

Electron ionisation mass spectrometry of the pentafluoropropionate esters of trichothecene analogues and culmorin compounds from Fusarium species.

Wenche Langseth et al.

Rapid communications in mass spectrometry : RCM, 24(17), 2641-2649 (2010-08-27)

This paper reports the mass spectra, obtained after electron ionisation (EI) at 70 eV, of 34 trichothecenes and five culmorin compounds after acylation with pentafluoropropionic anhydride. The derivatised fungal metabolites were separated by gas chromatography, and the mass spectra were

Atmospheric degradation of perfluoro-2-methyl-3-pentanone: photolysis, hydrolysis and hydration.

Derek A Jackson et al.

Environmental science & technology, 45(19), 8030-8036 (2011-04-07)

Perfluorinated carboxylic acids are widely distributed in the environment, including remote regions, but their sources are not well understood. Perfluoropropionic acid (PFPrA, CF(3)CF(2)C(O)OH) has been observed in rainwater but the observed amounts can not be explained by currently known degradation

Determination of N-methyl-1,3-propanediamine in bovine muscle by liquid chromatography with triple quadrupole and ion trap tandem mass spectrometry detection.

Clare Ho et al.

Journal of chromatography. A, 1235, 103-114 (2012-03-20)

Morantel, pyrantel and their drug-related metabolites in food of animal-origin are regulated as sum of residues which may be hydrolysed to N-methyl-1,3-propanediamine (NMPA). In this study, an isotope dilution liquid chromatography tandem mass spectrometry (LC-MS/MS) method with pentafluoropropionic acid anhydride

Light-induced degradation of perfluorocarboxylic acids in the presence of titanium dioxide.

Ralf Dillert et al.

Chemosphere, 67(4), 785-792 (2006-11-28)

The UV-photon-induced degradation of heptafluorobutanoic acid was investigated in acidic aqueous solutions in the presence of titanium dioxide. Heptafluorobutanoic acid could be degraded with this photocatalyst in a light-induced reaction generating carbon dioxide and fluoride anions. Carbon dioxide evolution in

[Recent development of C-terminal sequence analysis of proteins].

A Tsugita

Tanpakushitsu kakusan koso. Protein, nucleic acid, enzyme, 43(7), 857-865 (1998-06-23)

Limitations of porous graphitic carbon as stationary phase material in the determination of catecholamines.

Sandra Rinne et al.

Journal of chromatography. A, 1119(1-2), 285-293 (2006-03-21)

A fast and sensitive capillary liquid chromatography (cLC) column-switching method with electrospray ionization time-of-flight mass spectrometry (ESI-TOF-MS) detection for the simultaneous determination of dopamine (D), epinephrine (E), norepinephrine (NE) and serotonin (SE) was pursued. A sample volume of 100 microl

Determination of fentanyl, metabolite and analogs in urine by GC/MS.

Sabina Strano-Rossi et al.

Journal of applied toxicology : JAT, 31(7), 649-654 (2010-12-07)

A rapid and sensitive method for the simultaneous determination of alfentanyl, sufentanyl and fentanyl (and its major metabolite norfentanyl) in urine was developed and validated. The method involved a liquid-liquid extraction in alkaline conditions, derivatization with pentafluoropropionic anhydride to improve

Pentafluoropropionyl and trifluoroacetyl groups for temporary hydroxyl group protection in oligomannoside synthesis.

Maki Takatani et al.

Carbohydrate research, 338(10), 1073-1081 (2003-04-23)

Pentafluoropropionyl (PFP) and trifluoroacetyl (TFA) esters were demonstrated to be useful in facile oligosaccharide synthesis. These were well compatible with glycosylation conditions and removable by treatment with pyridine-EtOH, with complete preservation of acetyl groups. Analytically pure products were obtained quantitatively

Determination of 17 beta-estradiol and its metabolites in sewage effluent by solid-phase extraction and gas chromatography/mass spectrometry.

H B Lee et al.

Journal of AOAC International, 81(6), 1209-1216 (1998-12-16)

The paper describes a simple and quantitative method for monitoring non-conjugated 17 beta-estradiol (E2) and its metabolites estrone (E1) and estriol (E3) as environmental contaminants in municipal sewage effluents. Estrogens were preconcentrated and cleaned up by solid-phase extraction using a

Mass spectrometric characterization of gentamicin components separated by the new European Pharmacopoeia method.

B Li et al.

Journal of pharmaceutical and biomedical analysis, 55(1), 78-84 (2011-02-15)

Liquid chromatography combined with pulsed electrochemical detection (LC-PED) is the method of choice in the European Pharmacopoeia for the determination of gentamicin and its related substances. A recently approved improved LC-PED method, with a reversed-phase C(18) column and a mobile

Application of perfluorinated acids as ion-pairing reagents for reversed-phase chromatography and retention-hydrophobicity relationships studies of selected beta-blockers.

J Flieger

Journal of chromatography. A, 1217(4), 540-549 (2009-12-09)

The addition of the homologous series of perfluorinated acids-trifluoroacetic acid (TFAA), pentafluoropropionic acid (PFPA), heptafluorobutyric acid (HFBA) to mobile phases for reversed-phase high-performance liquid chromatography (RP-HPLC) of beta-blockers was tested. Acidic modifiers were responsible for acidification of mobile phase (pH

Improved liquid chromatographic method with pulsed electrochemical detection for the analysis of gentamicin.

Vicky Manyanga et al.

Journal of chromatography. A, 1189(1-2), 347-354 (2008-01-18)

The official method for the determination of the composition and related substances of gentamicin prescribed by the European Pharmacopoeia (Ph. Eur.) is liquid chromatography combined with pulsed electrochemical detection (LC-PED). However, this method utilizes a polymer stationary phase which shows

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