共查询到20条相似文献,搜索用时 15 毫秒
1.
P.J.M. Sessink M.M. Scholtes R.B.M. Anzion R.P. Bos 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1993,616(2)
A sensitive gas chromatographic method for the determination of cyclophosphamide in urine is presented. After liquid—liquid extraction with diethyl ether and derivatization with trifluoroacetic anhydride, cyclophosphamide was identified and quantified with mass spectrometry. The method is suitable for the determination of cyclophosphamide at concentrations of more than 0.25 ng/ml, which enables the uptake of cyclophosphamide during occupational activities, such as the preparation and administration of antineoplastic agents in hospitals, to be measured. Simple preparation makes the method appropriate for routine analysis. 相似文献
2.
Toyokazu Ohki Akira Saito Kazuhiro Ohta Toshimitsu Niwa Kenji Maeda Jinsaku Sakakibara 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1982,233(1):1-8
A method for the simultaneous analysis of phenolic amines and aliphatic amines in human urine is described. The amine metabolites in urine were extracted using Dowex 50W-X8 cationic resin, derivatized and analyzed by a gas chromatographic—mass spectrometric—computer system. The amine metabolites profile of 5 ml of urine was obtained with good gas chromatographic separation. The gas chromatographic method described here separates urinary phenolic amines, di- and polyamines and methylguanidine in a single chromatographic separation. The urinary levels of methylguanidine, putrescine, cadaverine, spermidine, p-tyramine, dopamine, and 3-methoxytyramine were quantitated by using a mass spectrometric technique. In uremic patients, only the urinary excretion of methylguanidine was increased in comparison with normal subjects, although the urinary excretion of other amines was decreased in uremic patients. 相似文献
3.
4.
Mirjam S. Leloux Ed G. De Jong Robert A. A. Maes 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1989,488(2)
An improved screening method for beta-blockers in urine is proposed, involving enzymatic hydrolysis, solid-phase extraction and capillary gas chromatography—mass spectrometry. Several extraction methods for beta-blockers, such as conventional liquid—liquid and solid-phase extraction procedures, have been evaluated for at least eight beta-blockers. Additionally, the gas chromatographic properties and mass fragmentation of the trimethylsilyl—trifluoroacetyl, trifluoroacetyl and cyclic n-butylboronate derivatives of beta-blockers have been compared and evaluated with respect to their efficiency for screening urine. The resulting screening method proved to be a specific and sensitive procedure, enabling these analytes to be detected and identified up to 48 h after the administration of a dosage, usually encountered in doping cases. 相似文献
5.
David J. Edwards Marguerite Rizk John Neil 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1979,164(4):407-416
A method is described for the determination of the neutral metabolites formed from catecholamines and various other structurally related phenylethylamines by using gas chromatography—chemical ionization—mass spectrometry. These metabolites (phenylglycols and phenylethanols) were extracted from urine specimens and converted to pentafluoropropionyl derivatives which were separated on either 3% OV-1, 3% SP-2250, or 3% QF-1 packed columns. Our results demonstrate the presence in human urine of p-hydroxyphenylglycol, a metabolite of octopamine. One patient excreted 13 and 91 μg/day of free and total (free + conjugated) p-hydroxyphenylglycol, respectively. Treatment with a monoamine oxidase inhibitor reduced the excretion of total p-hydroxyphenylglycol to 30% of baseline level. 相似文献
6.
Man Ho Choi Young Sock Yoo Bong Chul Chung 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2001,754(2)
An efficient method for the determination of testosterone and pregnenolone in human nails using gas chromatography–mass spectrometry (GC–MS) with d3-testosterone as an internal standard is described. The method involves alkaline digestion and liquid–liquid extraction, with subsequent conversion to mixed pentafluoropenyldimethylsilyl-trimethylsilyl (flophemesyl-TMS) derivatives for sensitive analysis in the selected-ion monitoring (SIM) mode. The limit of detection (LOD) and limit of quantification (LOQ) were lowered to 0.1 and 0.2 pg/g, respectively, when 100 mg of nail-clippings were used. The mean recoveries of testosterone and pregnenolone were 89.8 and 86.7%, respectively, while good overall precision (% C.V.; 4.5–9.5) and accuracy (% bias; 3.9–8.4) were demonstrated. Linearity as a correlation coefficient was 0.9913 (testosterone) and 0.9965 (pregnenolone). When applied to fingernail and toenail samples from seven healthy men and nine healthy women, testosterone and pregnenolone were positively detected in the concentration range of 0.24–5.80 ng/g. The levels of two steroids studied in the nails were found to be higher in the male subjects than in the female subjects, and except for the toenails of the females, the levels of testosterone were higher than those of pregnenolone. 相似文献
7.
J.M. Halket P.J. Watkins A. Przyborowska B.L. Goodwin A. Clow V. Glover M. Sandler 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1991,562(1-2)
A simple procedure based upon capillary column gas chromatography-mass spectrometry (GC—MS) is described for the detection and determination of isatin (indole-2,3-dione) in body fluids and tissues. After addition of 5-methylisatin as internal standard to urine or tissue homogenates, organic extracts are dried and derivatized successively with hydroxylamine hydrochloride and the reagent N-tert.-butyldimethylsilyl-N-methyltrifluoroacetamide (MTBSTFA). The tert.-butyldimethylsilyl derivatives obtained show good GC—MS properties and allow quantification by selected-ion monitoring of m/z 333 (isatin) and m/z 347 (internal standard). Adult and newborn human urine output values lie in the ranges 0.4–3.2 mg/mmol of creatinine (5–30 mg per 24 h) and 0.002–0.518 mg/mmol of creatinine, respectively. There is a discontinuous regional distribution in rat tissues. The GC—MS properties of a number of derivatives formed by successive reaction of isatin with hydroxylamine hydrochloride (or methoxyaminehydrochloride or ethoxyamine hydrochloride) and MTBSTFA, bis(trimethylsilyl)trifluoroacetamide, pentafluoropropionic anhydride or pentafluorobenzyl bromide are also described. 相似文献
8.
Maria-Helen E Spyridaki Christina J Tsitsimpikou Panayotis A Siskos Costas G Georgakopoulos 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2001,758(2):2098
A selective gas–liquid chromatographic method with mass spectrometry (GC–MS) for the simultaneous confirmation and quantification of ephedrine, pseudo-ephedrine, nor-ephedrine, nor-pseudoephedrine, which are pairs of diastereoisomeric sympathomimetic amines, and methyl-ephedrine was developed for doping control analysis in urine samples. O-Trimethylsilylated and N-mono-trifluoroacetylated derivatives of ephedrines — one derivative was formed for each ephedrine — were prepared and analyzed by GC–MS, after alkaline extraction of urine and evaporation of the organic phase, using d3-ephedrine as internal standard. Calibration curves, with r2>0.98, ranged from 3.0 to 50 μg/ml depending on the analyte. Validation data (specificity, % RSD, accuracy, and recovery) are also presented. 相似文献
9.
E. Daeseleire A. De Guesquire C. Van Peteghem 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1991,564(2)
A method for the detection of ethinylestradiol in cattle urine is described, based on enzymic hydrolysis of the sample, clean-up by means of disposable octadecyl and amino solid-phase extraction columns, fractionation by reversed-phase high-performance liquid chromatography, and detection by gas chromatography—mass spectrometry (selected-ion monitoring). Identification is based on both gas chromatographic and mass spectrometric data. The method has been tested on urine samples for a collaborative study and all the results found were correct. 相似文献
10.
Robert M. Gorsen A.J. Weiss R.W. Manthei 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1980,221(2):309-318
Twelve compounds representing procarbazine, seven metabolites, and an internal standard were analyzed by gas chromatography—mass spectrometry on a 3% OV-1 column. Procarbazine and four metabolites were derivatized with acetic anhydride.A sensitive, specific and quantitative assay was established by selected ion monitoring using a synthetic analogue of the drug as an internal standard. The limits of detection were approximately 1 ng/ml of plasma while the limits of quantitation were 10 ng/ml of plasma.Studies on the degradation of procarbazine - HCl in 0.05 M phosphate buffer (pH 7.4) were compared to in vivo studies. At 1 h after incubation of procarbazine - HCl in buffer, the azo and aldehyde metabolites were detected in the highest concentrations representing 27.2% and 20.3% of total drug and metabolites. In the in vivo studies, analyses of rat plasmas indicated that 1 h after an oral dose of procarbazine - HCl, the aldehyde metabolite represented 72% of the total drug and metabolites, and that relatively little of the azo metabolite was present. 相似文献
11.
A. Polettini M. C. Ricossa A. Groppi M. Montagna 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1991,564(2)
A rapid and reliable gas chromatographic—mass spectrometric method for the determination of clenbuterol in urine is described. Penbutolol was used as internal standard. Four derivatization procedures have been tested, of which 1-butaneboronic acid gave the best results. The method includes extraction of the alkalinized urine (3 ml) with tert.-butyl methyl ether—n-butanol (9:1), derivatization with 1-butaneboronic acid (15 min at room temperature), and analysis in the selected-ion monitoring mode of the derivatives of clenbuterol at m/z 243, 327 and 342 and of penbutolol at m/z 342 and 357. The detection limit is 0.5 ng/ml and the recovery better than 90%. 相似文献
12.
Juha Kokkonen Antti Leinonen Jari Tuominen Timo Seppl 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1999,734(2):2149
In doping control laboratories the misuse of anabolic androgenic steroids is commonly investigated in urine by gas chromatography–low-resolution mass spectrometry with selected ion monitoring (GC–LRMS–SIM). By using high-resolution mass spectrometry (HRMS) detection sensitivity is improved due to reduction of biological background. In our study HRMS and LRMS methods were compared to each other. Two different sets were measured both with HRMS and LRMS. In the first set metandienone (I) metabolites 17α-methyl-5β-androstan-3α,17β-diol (II), 17-epimetandienone (III), 17β-methyl-5β-androst-1-ene-3α,17α-diol (IV) and 6β-hydroxymetandienone (V) were spiked in urine extract prepared by solid-phase extraction, hydrolysis with β-glucuronidase from Escherichia coli and liquid–liquid extraction. In the second set the metabolites were first spiked in blank urine samples of four male persons before pretreatment. Concentration range of the spiked metabolites was 0.1–10 ng/ml in both sets. With HRMS (resolution of 5000) detection limits were 2–10 times lower than with LRMS. However, also with the HRMS method the biological background hampered detection and compounds from matrix were coeluted with some metabolites. For this reason the S/N values of the metabolites spiked had to be first compared to S/N values of coeluted matrix compounds to get any idea of detection limits. At trace concentrations selective isolation procedures should be implemented in order to confirm a positive result. The results suggest that metandienone misuse can be detected by HRMS for a prolonged period after stopping the intake of metandienone. 相似文献
13.
14.
Kenji Maeda Shunsuke Kawaguchi Toshimitsu Niwa Toyokazu Ohki Kaizo Kobayashi 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1980,221(2):199-204
A gas chromatographic—mass spectrometric analysis was used to separate and identify abnormal compounds in the nail of psoriatic patients. The nail was extracted with heated ethanol, and the extract was analyzed with and without trimethylsilylation. Tetradecanoic acid octadecyl ester, hexadecanoic acid octadecyl ester and octadecanoic acid octadecyl ester were first identified in the psoriatic nail, but were not detected in normal nail. 相似文献
15.
M. Axelson B.-L. Sahlberg J. Sjvall 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1981,224(3):355-370
A simplified, flexible method for the analysis of metabolic profiles of steroids in urine is described. Solid extraction with Amberlite XAD-2 or Sep-Pak C1 g cartridges is followed by group fractionation of unconjugated neutral and phenolic steroids, monoglucuronides, monosulphates and disulphates on the lipophilic strong anion exchanger triethylaminohydroxyproply Sephadex LH-20 (TEAP-LH-20). Following brief enzymatic hydrolysis or solvolysis the steroids are purified on TEAP-LH-20. O-Methyloxime and trimethylsilyl ether derivatives are prepared and purified by filtration through Lipidex 5000, and are then analyzed by glass capillary column gas—liquid chromatography and gas chromatography—mass spectrometry.Between 2 and 5 ml of urine are used for a comprehensive analysis. Unconjugated neutral and phenolic steroids are isolated in half a day, corresponding steroids in the conjugate fractions in two days. No fraction containing steroids is discarded, but the analysis can be limited to a selected fraction. 相似文献
16.
17.
S. Pavel F.A.J. Muskiet G.T. Nagel Z. Schwippelov J. Ducho 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1981,222(3):329-336
The isolation of two Thormählen-positive compounds from the urine of a patient with malignant melanoma and the elucidation of their structure by gas chromatography—mass spectrometry is described. The compounds were isolated using a poly-N-vinylpyrrolidone column and separated by preparative thin-layer chromatography. After elution they were analyzed by gas chromatography and gas chromatography—mass spectrometry as their trimethylsilyl derivatives and after hydrolysis also as their tert.-butyldimethylsilyl derivatives. The results showed the main Thormählen-positive compound A to be the glucuronide of 5-hydroxy-6-methoxyindole, whereas the minor compound AX appeared to be the glucuronide of its isomer 6-hydroxy-5-methoxyindole. 相似文献
18.
P.L. Stetson E.F. Domino J.R. Sneyd 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1993,620(2):260-267
Propofol (2,6-diisopropylphenol, I.C.I. 35 868) is a rapid-acting, intravenous anesthetic agent recently introduced for the induction and maintenance of general anesthesia. This paper describes a gas chromatographic—mass spectrometric procedure using selected-ion monitoring for the determination of plasma propofol levels. The drug and the internal standard (thymol) were extracted from plasma into diethyl ether—pentane, and derivatized to their trimethylsilyl derivatives before analysis. The reproducibility of the daily standard curves had coefficients of variation ranging from 2.7% to 10.2%. The precision of the assay yielded a coefficient of variation ranging from 4.5% to 5.6%, and the concentration means for the seeded control samples were found to be within −1.6% to +0.6% of the theoretical values for propofol. No interfering peaks have been observed in application of this procedure to either normal volunteer or patient samples. The minimum detectable level under the conditions described was 0.20 ng propofol/ml plasma. This assay and a high-performance liquid chromatographic assay with fluorescence detection were both used to measure plasma propofol concentrations in 89 human plasma samples, and the correlation between the two methods was excellent. 相似文献
19.
20.
Suresh K. Aggarwal Michael Kinter David A. Herold 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1992,576(2)
A gas chromatographic—mass spectrometric method for the determination of cobalt in biological materials employing stable enriched 62Ni as an internal standard and using lithium bis(trifluoroethyl)dithiocarbamate as a chelating agent is described. The method involves the addition of a known amount (1 μg) of 62Ni to the sample, the formation of the chelate and the determination by selected-ion monitoring of the m/z ratio, which corresponds to . No appreciable memory effect was observed, and an acceptable dynamic range of 100 was found. There was good agreement between the cobalt concentration values determined by gas chromatography—mass spectrometry and electrothermal atomic absorption spectrometry. The present method has high sensitivity and can be used for the quantitation of cobalt at concentrations as low as 1 μg/l. The use of enriched 62Ni circumvents the problem caused by endogenous nickel and simultaneously provides data on the nickel concentration in the biological sample without any additional experimental effort. 相似文献