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1.
M. A. Dikunets S. A. Appolonova G. M. Rodchenkov 《Journal of Analytical Chemistry》2009,64(8):832-842
A procedure was developed for screening 23 corticosteroids, 12 anabolic steroids, 23 diuretics, and 49 central nervous system stimulants and narcotics. The sample preparation includes extraction, the evaporation of the organic extract in a nitrogen flow, and the dissolution of the dry residue. The extract was analyzed by high-performance liquid chromatography-tandem mass spectrometry with atmospheric pressure electrospray ionization under different recording conditions. Negatively charged ions were recorded to determine corticosteroids and diuretics, while positively charged ions, to determine anabolic steroids, diuretics, stimulants, and narcotics. Mass spectra were obtained for all test compounds; the characteristic ions, retention times, detection limits, degree of ionization suppression by the matrix, and recovery were determined for all analytes. 相似文献
2.
Vortex‐assisted liquid–liquid microextraction for the rapid screening of short‐chain chlorinated paraffins in water
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The rapid screening of trace levels of short‐chain chlorinated paraffins in various aqueous samples was performed by a simple and reliable procedure based on vortex‐assisted liquid–liquid microextraction combined with gas chromatography and electron capture negative ionization mass spectrometry. The optimal vortex‐assisted liquid–liquid microextraction conditions for 20 mL water sample were as follows: extractant 400 μL of dichloromethane; vortex extraction time of 1 min at 2500 × g; centrifugation of 3 min at 5000 × g; and no ionic strength adjustment. Under the optimum conditions, the limit of quantitation was 0.05 μg/L. Precision, as indicated by relative standard deviations, was less than 9% for both intra‐ and inter‐day analysis. Accuracy, expressed as the mean extraction recovery, was above 91%. The vortex‐assisted liquid–liquid microextraction with gas chromatography and electron capture negative ionization mass spectrometry method was successfully applied to quantitatively extract short‐chain chlorinated paraffins from samples of river water and the effluent of a wastewater treatment plant, and the concentrations ranged from 0.8 to 1.6 μg/L. 相似文献
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Hopley CJ Stokes P Webb KS Baynham M 《Rapid communications in mass spectrometry : RCM》2004,18(10):1033-1038
A method for the analysis of thyroxine in human serum, utilising 'exact matching' isotope dilution mass spectrometry (IDMS) in combination with liquid chromatography/tandem mass spectrometry (LC/MS/MS), has been developed with a limit of quantification of 0.5 ng g(-1) of thyroxine in human serum. The extraction and clean-up of thyroxine from serum involves an efficient protein-precipitation stage followed by a solid-phase extraction procedure to produce an extract essentially free from interfering compounds. The method is reproducible, with expanded uncertainties of less than 2%, and is relatively fast to perform. 相似文献
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In a novel procedure, human serum albumin timctionalized magnetic nanoparticles ( HSA-MNPS ) were used to selectively extract nine flavonoids in the extract of Ginkgo biloba leaves. The chemical structures of those flavonoids were characterized with high performance liquid chromatography coupled with mass spectrometry (HPLC-MS). The selective extraction with HSA-MNPs coupled with structural elucidation with HPLC-MS shows powerful potential for analysis of bioactive components in traditional Chinese medicines. 相似文献
7.
An analytical procedure for the determination of natural steroids and their conjugates was developed and applied to bovine and human urine. Fifteen compounds (free and conjugated) after extraction by solid-phase were identified by liquid chromatography-tandem mass spectrometry (LC-MS-MS) in multiple reaction monitoring (MRM). Free and conjugated steroids were detected all together in the same chromatographic analysis respectively in positive and negative ionization. This procedure reveals to be time-saving, because it overcomes the need of further sample pre-treatment steps, such as enzymatic hydrolysis and derivatisation.The recovery for each compound was around 80%. Limit of detection of each steroid free or conjugated has been evaluated. 相似文献
8.
Georgakopoulos CG Vonaparti A Stamou M Kiousi P Lyris E Angelis YS Tsoupras G Wuest B Nielen MW Panderi I Koupparis M 《Rapid communications in mass spectrometry : RCM》2007,21(15):2439-2446
A new combined doping control screening method for the analysis of anabolic steroids in human urine using liquid chromatography/electrospray ionization orthogonal acceleration time-of-flight mass spectrometry (LCoaTOFMS) and gas chromatography/electron ionization orthogonal acceleration time-of-flight mass spectrometry (GCoaTOFMS) has been developed in order to acquire accurate full scan MS data to be used to detect designer steroids. The developed method allowed the detection of representative prohibited substances, in addition to steroids, at concentrations of 10 ng/mL for anabolic agents and metabolites, 30 ng/mL for corticosteroids, 500 ng/mL for stimulants and beta-blockers, 250 ng/mL for diuretics, and 200 ng/mL for narcotics. Sample preparation was based on liquid-liquid extraction of hydrolyzed human urine, and the final extract was analyzed as trimethylsilylated derivatives in GCoaTOFMS and underivatized in LCoaTOFMS in positive ion mode. The sensitivity, mass accuracy, advantages and limitations of the developed method are presented. 相似文献
9.
A novel method for the determination of five kinds of mercapturic acids, found in urine as metabolites of alkylbenzenes, based on liquid chromatography-electrospray ionization mass spectrometry is described. A solid-phase extraction procedure was used for the extraction of the mercapturic acids from urine and the separation was performed on a reversed-phase C30 column. The detection limits were in the range 2.4-3.2 ng ml-1. 相似文献
10.
Sørensen LK 《Biomedical chromatography : BMC》2012,26(1):1-5
Metformin is an anti-diabetic drug in the biguanide class which also includes phenformin and buformin. Because of the potential adverse effects of the biguanides, a reliable liquid chromatography-tandem mass spectrometry method using pneumatically assisted electrospray ionization was developed for the quantification of the drugs in both live and post-mortem human whole blood. The blood proteins were precipitated by the addition of a mixture of methanol and acetonitrile, and the extract was cleaned up by cation-exchange solid-phase extraction to eliminate ion suppression effects. The separation was performed by hydrophilic interaction liquid chromatography. Matrix-matched calibrants combined with isotope dilution of metformin were used for calibration. The detection limits were 0.01 mg/L for metformin and phenformin and the relative intra-laboratory reproducibility standard deviations were less than 6% at concentrations of 1-10 mg/L. The mean true recoveries were greater than 86%. 相似文献
11.
A new method was developed for the analysis of pesticide residues in tobacco. The objective was to significantly increase the number of samples that can be processed by the laboratory and to enable the extension of the current coverage to additional pesticides. A new analytical approach was therefore defined based on two main axes, the automation of the sample preparation and the selectivity of the analyte detection using tandem mass spectrometry. This latter aspect reduces the stringency of the requirements placed on the clean-up of the extracts and on the chromatographic resolution when less selective detectors are used. The extraction of the analytes from the matrix is performed using the pressurized liquid extraction technique. Tobacco samples are extracted at elevated temperature and pressure (100 C and 100 atm; 1 atm = 101,325 Pa) using acetone as an extraction solvent. The resulting extract is then concentrated using a Vortex evaporator. Three different solid-phase extraction (SPE) procedures, adjusted to the chemical properties of the different active ingredients to be measured, are applied to the concentrated extract, thus leading to three extract fractions. The first fraction contains such main classes of active ingredients as organohalogenated and 2,6-dinitroaniline compounds while the second one collects the organophosphorus and acylalanines residues; these two fractions are analyzed by capillary gas chromatography coupled to tandem mass spectrometry using negative chemical ionization and electron impact ionization in the positive mode, respectively. The third extract fraction gathers the N-methylcarbamates residues which are analyzed by HPLC with post-column derivatization and fluorescence detection. The different sample preparation stages from extraction to SPE clean-up have been automated through the use of recent analytical technologies. In combination with the analysis by tandem mass spectrometry, this provided a potential for a high sample throughput. 相似文献
12.
J Girault B Istin J M Malgouyat A M Brisson J B Fourtillan 《Journal of chromatography. A》1991,564(1):43-53
A new simple and sensitive assay has been developed for the simultaneous quantitative measurement of beclomethasone dipropionate and its hydrolysis products in human plasma and urine. Beclomethasone 17.21-dipropionate, beclomethasone 17-monopropionate, beclomethasone and the internal standard, dexamethasone 21-acetate, were measured by combined liquid chromatography and negative-ion chemical ionization mass spectrometry with methane as the reagent gas. A particle beam interface from Hewlett Packard was used. Under mild operating conditions, abundant and stable characteristic high-mass ions were generated in the ion source of the mass spectrometer by a resonance electron-capture mechanism. The fast extraction procedure requires 1 ml of plasma or urine, and the quantification limit of the method is 1 ng ml-1 for the three tested compounds. 相似文献
13.
Trufelli H Famiglini G Termopoli V Cappiello A 《Analytical and bioanalytical chemistry》2011,400(9):2933-2941
This paper focuses on the development of a novel approach to analyze underivatized fatty acids in human plasma. The method
is based on liquid–liquid extraction followed by reversed phase liquid chromatography coupled to direct-electron ionization
mass spectrometry (LC-Direct-EI-MS). The assay is validated. Calibrations show satisfactory linearity and precision in the
investigated range of linearity. Recoveries span from 75% to 104%. The method limits of detection, varying from 0.53 to 5.35 μM,
are satisfactory for the quantitation of non-esterified fatty acids (NEFAs) in plasma at physiological levels. The method
has been successfully applied to the NEFAs profiling of plasma samples from healthy adult volunteers and subjects affected
by diabetes mellitus. Compared with published protocols based on gas chromatography–mass spectrometry and liquid chromatography
coupled to electrospray ionization mass spectrometry, this method does not require derivatization and does not show matrix
effects, thus simplifying sample preparation procedure and reducing the total time of analysis to approximately 90 min. In
addition, Direct-EI-MS allows the acquisition of high-quality NIST library-matchable EI spectra, allowing an easy-to-obtain
identification of the target NEFAs. 相似文献
14.
A quantitative acetonitrile extraction with dispersive solid-phase clean-up and subsequent high performance hydrophilic interaction liquid chromatography-atmospheric pressure electrospray ionization mass spectrometry (HILIC-ESI-MS-MS) analysis is outlined for the determination of propylenethiourea (PTU, 4-methylimidazolidine-2-thione), the main degradation product of propylenebisdithiocarbamate (PBDC). In the present study, the quick, easy, cheap, effective, rugged and safe method (QuEChERS) methodology was adopted for the extraction of PTU from tomato matrix. The synthesis and impurity profiling of a new internal standard compound (4,5-dimethylimidazolidine-2-thione) is also reported, which was used instead of tris(1,3-dichlorisopropyl)phosphate due to poor ionization at elevated acetonitrile levels. The effect of chromatographic parameters on the HILIC separation and MS detection was studied. Coupling of hydrophilic interaction liquid chromatography with mass spectrometric detection was advantageous not only in view of separation and ionization efficiency but also in direct injection of the QuEChERS extract without the need for solvent exchange. 相似文献
15.
I. I. Sukhanova M. A. Dikunets E. D. Viryus G. M. Rodchenkov 《Journal of Analytical Chemistry》2011,66(9):807-814
A new version of extraction is proposed for the extraction of doping substances from urine. It is based on magnetic separation
using ferromagnetic microparticles with the surface modified with C18 groups. A procedure is developed on its basis for the quantification of selective modulators of androgen receptors and peroxisome
proliferator-activated delta-receptor agonists using high-performance liquid chromatography coupled with tandem mass spectrometry.
Using the proposed approach, the recovery of doping substances from human biological fluids approximates 100%, while the negative
effect of the matrix components on the ionization of target compounds is reduced to a minimum. In contrast to solid phase
extraction and liquid-liquid extraction, the method of magnetic separation appears to be more rapid and simple. The time of
pretreatment for a sample intended for HPLC coupled to tandem mass spectrometry makes 5 min; the detection limit makes 0.25–5
ng/mL. 相似文献
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Determination of tetracyclines in bovine kidney by liquid chromatography/tandem mass spectrometry with on-line extraction and clean-up 总被引:2,自引:0,他引:2
Van Eeckhout N Perez JC Claereboudt J Vandeputte R Van Peteghem C 《Rapid communications in mass spectrometry : RCM》2000,14(4):280-285
A novel, sensitive, high performance liquid chromatography/tandem mass spectrometric (i.e. mass spectrometry/mass spectrometry) method with on-line extraction and clean-up for the screening and confirmation of residues of tetracyclines in kidney has been developed. After liquid extraction of homogenised kidney with McIlvain buffer, an aliquot of the extract is directly injected on the LC/MS/MS system with further extraction and clean-up of the sample on-line. Detection of the analytes was achieved by positive electrospray ionization followed by multiple reaction monitoring. For each tetracycline the collisional decomposition of the protonated molecule to a unique, abundant fragment ion was monitored. The method has been validated for tetracycline, oxytetracycline, chlortetracycline and doxycycline. Calibration curves resulting from spiked blank kidney samples at the 100-1200 microgram/kg level showed good linear correlation. At the level of 600 microgram/kg both within- and between-day precision, as measured by relative standard deviation (RSD), were less than 7%. The limits of detection (LODs) for tetracycline, oxytetracycline, chlortetracycline and doxycyline were 18, 23, 24 and 21 microgram/kg, respectively. The limits of quantification (LOQs) for tetracycline, oxytetracycline, chlortetracycline and doxycyline were 36, 46, 47 and 42 microgram/kg, respectively. The recoveries ranged from 71 to 91%. The procedure provides a rapid, reliable and sensitive method for the determination of residues of tetracyclines in bovine kidney. The advantage of this method over existing methods is its decreased sample preparation and analysis time, which makes the method more suitable for routine analysis. 相似文献
18.
超高效液相色谱-串联质谱法同时测定调味料中的17种防腐剂和抗氧化剂 总被引:1,自引:0,他引:1
建立了超高效液相色谱-串联质谱(UPLC-MS/MS)同时测定调味料中11种防腐剂和6种抗氧化剂的定性、定量分析方法。低脂肪和中等脂肪含量的调味料样品用饱和NaCl水溶液(用磷酸调pH为2~3)稀释混合均匀,然后用乙腈提取,正己烷液-液萃取净化(中等脂肪含量的样品提取液还需经C8固相萃取柱进一步的净化处理);脂肪含量高的样品先用正己烷稀释,再用饱和NaCl水溶液(用磷酸调pH为2~3)溶解样品,然后用乙腈提取,提取液进一步经C8固相萃取柱净化处理。提取液经C18反相色谱柱(150 mm×2.1 mm, 1.7μm)分离,流动相为20 mmol/L乙酸铵水溶液和乙腈,梯度洗脱,以电喷雾离子源负离子多反应监测(MRM)模式进行MS/MS检测。17种分析物在线性范围内具有较好的线性关系,相关系数r≥0.9955,其定量限(LOQ,信噪比为10)为0.05~5 mg/kg;空白样品中的添加回收率为79.7%~118%,精密度(以相对标准偏差计)为0.57%~13.1%。该方法适用于调味品中防腐剂和抗氧化剂的检测。 相似文献
19.
This research extends previous studies regarding the application of supercritical fluid extraction (SFE) for the analysis of oligomers from nylon 6,6 fibers. The effects of CO2 pressure, extraction temperature, CO2-modifier percentage, static extraction time and dynamic extraction time on the SFE efficiency of nylon 6,6 oligomers were examined. Results from the SFE methods for oligomer extractions were compared to results from conventional solvent extraction. The extracted oligomers were identified by high-performance liquid chromatography (HPLC) with coupled on-line atmospheric pressure chemical ionization mass spectrometry and HPLC fractionation coupled with off-line liquid secondary ion mass spectrometry. 相似文献
20.
液相色谱-串联质谱法测定鸡组织中沃尼妙林残留 总被引:1,自引:0,他引:1
建立了鸡组织中沃尼妙林残留的液相色谱-电喷雾串联质谱(LC-ESI-MS /MS) 检测方法.样品用乙腈提取后,过Strata-X-C固相萃取小柱净化.以乙腈-0.1%甲酸水溶液(35∶ 65,V/V)为流动相,经Luna C18色谱柱分离,采用电喷雾电离,多反应监测(MRM)正离子模式对沃尼妙林进行定性与定量分析.采用基质匹配法,对鸡皮肤、肌肉、肾脏和肝脏中沃尼妙林的含量进行标准校正,在5(7.5)~500 μg/kg范围内线性良好(r>0 998),在鸡肝脏中的检出限(LOD)及定量限(LOQ)分别为4.0和7.5 μg/kg;其它3种组织中的LOD及LOQ分别为2.5和5.0 μg/kg.在5(7.5), 50及500 μg/kg添加水平下,4中组织中沃尼妙林的平均回收率为78 5%~104.0%.日内相对标准偏差(RSD)为1.2%~9.8%,日间相对标准偏差为3.7%~13.2%. 相似文献