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194484

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Vicente Ferreira et al.
Journal of chromatography. A, 1122(1-2), 255-265 (2006-05-20)
This work presents a thorough study of some aspects critical to the quantitative performance of methods for the determination of volatile aldehydes previously derivatized to pentafluorobenzyl hydroxylamine oximes. The conclusions of the study are further applied to the validation of
Y W Lin et al.
Applied occupational and environmental hygiene, 15(11), 855-862 (2000-11-04)
Ketones are the major positive interferences for an aldehyde dynamic air sampler that consists of 200-mg 20 percent (w/w) O-(2,3,4,5,6-pentafluorobenzyl)hydroxylamine hydrochloride (PFBHA) on Tenax TA contained in a Pyrex tube 7-mm OD, 5-mm ID, and 70-mm in length, that utilizes
S Friedfeld et al.
Geophysical research letters, 27(14), 2093-2096 (2002-01-05)
A one-week in situ intercomparison campaign was completed on the Rice University campus for measuring HCHO using three different techniques, including a novel optical sensor based on difference frequency generation (DFG) operating at room temperature. Two chemical derivatization methods, 2,4-dinitrophenylhydrazine
Petr Vesely et al.
Journal of agricultural and food chemistry, 51(24), 6941-6944 (2003-11-13)
A new, fast, sensitive, and solventless extraction technique was developed in order to analyze beer carbonyl compounds. The method was based on solid-phase microextraction with on-fiber derivatization. A derivatization agent, O-(2,3,4,5,6-pentafluorobenzyl)hydroxylamine (PFBOA), was absorbed onto a divinyl benzene/poly(dimethylsiloxane) 65-microm fiber
Chunhui Deng et al.
Journal of separation science, 28(2), 172-176 (2005-03-10)
A simple, rapid, sensitive, and solvent-free method was developed for determination of plant-signalling compounds, the three C6-aldehydes hexanal, (Z)-3-hexenal, and (E)-2-hexenal, in tomato plant emission by gas chromatography-mass spectrometry (GC-MS) and solid-phase microextraction (SPME) with on-fiber derivatization. In this method
T Gabrio et al.
Journal of chromatography. A, 1046(1-2), 293-296 (2004-09-25)
To avoid microbiological decay pool water is disinfected, a procedure which results into a lot of disinfection by-products, like carbonyl compounds, as well as a large number of others. The carbonyl compounds dissolved in pool water were derivatisized with O-(2,3,4,5,6-pentafluorobenzyl)hydroxyamine
Elena Gómez Alvarez et al.
Talanta, 88, 252-258 (2012-01-24)
A characterisation of a system designed for active sampling of gaseous compounds with Solid Phase Microextraction (SPME) fibres is described. This form of sampling is useful to automate sampling while considerably reducing the sampling times. However, the efficiency of this
D A Cancilla et al.
Journal of chromatography, 627(1-2), 1-16 (1992-12-25)
A review on the use of O-(2,3,4,5,6-pentafluorophenyl)methylhydroxylamine hydrochloride (PFBHA) for the determination of carbonyl-containing compounds is presented. PFBHA has been used in the determination of such diverse compounds as thromboxane B2, prostaglandins, amygdalin and a variety of other aldehydes, ketones
Fabienne Reisen et al.
Environmental science & technology, 39(12), 4447-4453 (2005-07-29)
Alkanes account for approximately 50% of nonmethane organic compounds present in urban atmospheres. Previous studies have shown that hydroxycarbonyls are important products ofthe OH radical initiated reactions of > or = C5 n-alkanes, but isomer-specific identifications and quantifications of these
Riccardo Flamini et al.
Journal of mass spectrometry : JMS, 40(12), 1558-1564 (2005-12-02)
A new method has been developed to determine acetaldehyde, 2,3-butanedione (diacetyl) and 3-hydroxy-2-butanone (acetoin) in wine by solid-phase microextraction (SPME) and positive ion chemical ionization GC/MS analysis of O-(2,3,4,5,6-pentafluorobenzyl)-hydroxylamine (PFBOA) derivatives. For SPME, a 65-microm PEG/DVB fibre was used; chemical
Yoichi Noya et al.
Toxicology, 314(1), 1-10 (2013-08-29)
Smoking is a major risk factor for atherosclerotic vascular diseases, but the mechanism for its genesis is unknown. We have recently shown that the gas phase of cigarette smoke (nicotine- and tar-free cigarette smoke extract; CSE) likely to reach the
P Spiteller et al.
Biochimica et biophysica acta, 1531(3), 188-208 (2001-04-28)
Lipid peroxidation (LPO) processes observed in diseases connected with inflammation involve mainly linoleic acid. Its primary LPO products, 9-hydroperoxy-10,12-octadecadienoic acid (9-HPODE) and 13-hydroperoxy-9,11-octadecadienoic acid (13-HPODE), decompose in multistep degradation reactions. These reactions were investigated in model studies: decomposition of either
Giuseppe Pieraccini et al.
Journal of chromatography. A, 955(1), 117-124 (2002-06-14)
Glutaraldehyde is used primarily in hospital environments for the disinfection of various instruments (e.g., endoscopes). We describe in this paper the measurement of glutaraldehyde in a hospital environment using solid-phase microextraction. The method includes, prior to sampling, the adsorption of
R S Spaulding et al.
Analytical and bioanalytical chemistry, 372(7-8), 808-816 (2002-05-16)
The employment of O-(2,3,4,5,6-pentafluorobenzyl)hydroxylamine (PFBHA) derivatization along with bis-(trimethylsilyl)trifluoroacetamide (BSTFA) or N, N-( tert-butyldimethylsilyl)trifluoroacetamide (MTBSTFA) derivatization is a popular method for measurement of oxygenated organics in environmental and biological samples. Most notably, the derivatization method enables the measurement of atmospheric
Julián Zapata et al.
Analytica chimica acta, 660(1-2), 197-205 (2010-01-28)
This work presents a comparative study of the analytical characteristics of two methods for the analysis of carbonyl compounds in wine, both based on the derivatization with O-(2,3,4,5,6-pentafluorobenzyl)hydroxylamine hydrochloride (PFBHA). In the first method derivatives are formed in the solid
Chunhui Deng et al.
Journal of chromatography. B, Analytical technologies in the biomedical and life sciences, 810(2), 269-275 (2004-09-24)
Analysis of breath acetone has been used as a diagnostic tool for diabetes. Due to its nature of volatility and activity, it is very difficult to accurately measure the concentration of acetone in human breath by gas chromatography-mass spectrometry (GC-MS).
Chunhui Deng et al.
Rapid communications in mass spectrometry : RCM, 19(5), 647-653 (2005-02-09)
In the current work, a simple, rapid, accurate and inexpensive method was developed for the determination of acetone in human blood. The proposed method is based on derivatization with O-(2,3,4,5,6-pentafluorobenzyl)hydroxylamine hydrochloride (PFBHA), followed by headspace liquid-phase microextraction (HS-LPME) and gas
S W Liou et al.
Bulletin of environmental contamination and toxicology, 80(4), 324-328 (2008-03-18)
This work studied the feasibility of using a solid phase microextraction (SPME) fiber for sampling and analysis of gaseous formaldehyde as well as particulate-bound formaldehyde from burning Chinese incense. The SPME fiber with PDMS/DVB coating were partially coated with o-(2,3,4,5,6-pentafluorobenzyl)-hydroxylamine
J R Wells
Environmental science & technology, 39(18), 6937-6943 (2005-10-06)
A bimolecular rate constant, kOH+alpha-terpineol, of (1.9 +/- 0.5) x 10(-10) cm3 molecule(-1) s(-1) was measured using gas chromatography/mass spectrometry and the relative rate technique for the reaction of the hydroxyl radical (OH) with alpha-terpineol (1-methyl-4-isopropyl-1-cyclohexen-8-ol) at (297 +/- 3)
K T Koshy et al.
Journal of chromatographic science, 13(2), 97-104 (1975-02-01)
0-(2,3,4,5,6-pentafluorobenzyl)hydroxylamine hydrochloride was used to prepare oximes of steroids with keto groups in selected positions; 3,17 and 20-monoketo; 3,17 and 3,20-diketo. Some of the 3-keto steroids had hindered 17-hydroxyl groups which were not readily amenable to esterification with perfluoroanhydrides, the
Bruce D Pacolay et al.
Journal of environmental monitoring : JEM, 10(7), 853-860 (2008-08-09)
Solid-phase microextraction (SPME) was evaluated for the detection and quantification of the gas-phase carbonyls: citronellal, glyoxal, methylglyoxal, and beta-ionone. Prepared air samples containing the carbonyl compounds were collected at a flow rate of 2.8 L min(-1) in an impinger containing
Christiane Collins et al.
Chemical research in toxicology, 16(12), 1560-1566 (2003-12-19)
Deoxyribose oxidation in DNA represents a biologically important facet of oxidative DNA damage that gives rise to protein-DNA cross-links and base adducts. Toward the goal of quantifying deoxyribose oxidation chemistry in cells, we report a method for the quantification of
Yun-Gon Kim et al.
Journal of chromatography. B, Analytical technologies in the biomedical and life sciences, 893-894, 177-181 (2012-03-31)
Nucleotide diphosphate (NDP) sugars are widely present in antibiotics and glycoconjugates, such as protein- and lipid-linked oligosaccharides, where they act as substrates for glycosyltransferase in eukaryotes and prokaryotes. Among NDP sugars, NDP-4-keto sugars are key intermediates in the synthesis of
Beatriz Cancho et al.
Journal of chromatography. A, 943(1), 1-13 (2002-02-01)
A headspace solid-phase microextraction (HS-SPME) procedure followed by gas chromatography and electron capture detection (GC-ECD) has been developed for the determination of aldehydes in drinking water samples at microg/l concentrations. A previous derivatization with o-(2,3,4,5,6-pentafluorobenzyl)hydroxylamine hydrochloride (PFBHA) was performed due
Catherine Tessini et al.
Journal of chromatography. A, 1219, 154-160 (2011-12-14)
HPLC-UV and GC/MS determination of aldehydes in bio-oil were evaluated. HPLC-UV preceded by derivatization with 2,4-dinitrophenylhydrazine allows separation and detection of bio-oil aldehydes, but the derivatization affected the bio-oil stability reducing their quantitative applicability. GC/MS determination of aldehydes was reached
E Gómez Alvarez et al.
Environmental science & technology, 41(24), 8362-8369 (2008-01-19)
The methodology of solid phase microextraction (SPME) with O-(2,3,4,5,6)-pentafluorobenzylhydroxylamine hydrochloride (PFBHA) on-fiber derivatization for the determination of carbonyls has been applied to the photo-oxidation of benzene and toluene carried out in the EUPHORE chambers. This work focuses on the results
Raya Ahmed et al.
Cell reports, 33(11), 108501-108501 (2020-12-17)
A central paradigm in the field of lymphocyte biology asserts that replicatively senescent memory T cells express the carbohydrate epitope CD57. These cells nonetheless accumulate with age and expand numerically in response to persistent antigenic stimulation. Here, we use in vivo deuterium
Birgit Schulze et al.
Analytical biochemistry, 348(2), 269-283 (2005-11-26)
A GC-MS-based method for the simultaneous quantification of common oxylipins along with labile and highly reactive compounds based on in situ derivatization with pentafluorobenzyl hydroxylamine to the corresponding O-2,3,4,5,6-pentafluorobenzyl oximes (PFB oximes) is presented. The approach covers oxo derivatives such
S Strassnig et al.
Journal of chromatography. A, 891(2), 267-273 (2000-10-24)
A method for the determination of carbonyl compounds, either directly from gaseous phase or following a volatilization from liquid or solid samples after trapping on Tenax TA is presented. Following solvent desorption, the carbonyls are derivatized using O-(2,3,4,5,6-pentafluorobenzyl)hydroxylamine. The reaction
B A Gallasch et al.
Lipids, 35(9), 953-960 (2000-10-12)
The previously unknown linoleic acid peroxidation product 9,12-dioxo-10(Z)-decenoic acid (Z5) was detected in lentil seed flour (Lens culinaris Medik.) by electron impact mass spectrometry (EI-MS) after derivatization with pentafluorobenzyl-hydroxylamine-hydrochloride, methylation of acidic groups with diazomethane, and protection of hydroxylic groups
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