血液中吗啡类毒品硅烷化气相色谱-质谱分析

建立和确证了血液中吗啡类毒品(吗啡、 6-单乙酰吗啡、可待因)的液相萃取-硅烷化-GC/MS-SIM检测的方法.以乙基吗啡为内标,以V(CHCl3)∶V(异丙醇)∶V(正庚烷)＝50∶17∶33混合溶剂为萃取溶剂,以MSTFA 为硅烷化试剂,采用GC/MS-SIM检测方式,吗啡、6-单乙酰吗啡、可待因的线性相关系数均大于0.99,最低血液检测浓度可达到5 ng/mL;定量范围10～1000 ng/mL;日内重复性小于15%.该方法可用于海洛因吸食者血液中的毒品及其代谢物的检验.     

Limits in arson debris analysis by capillary column gas chromatography/mass spectrometry

Sample enrichment technology and instrumental sensitivity are no longer limiting factors in arson debris analysis. When pyrolyzed, petroleum based composite materials may produce artifacts. Urban air is another major source of interference since some of the components typically found in air, in particular alkylated aromatic hydrocarbons, are customarily used as indicators for the presence of gasoline. It is suggested to replace qualitative analysis with a quantitative approach, taking the sample matrix into consideration.     

捕集阱顶空气相色谱/质谱法测定水中的二氯一溴甲烷

建立了捕集阱顶空气相色谱/质谱测定水中二氯一溴甲烷的方法。采用正交实验设计对平衡温度、平衡时间、循环次数3个参数进行了优化,在平衡温度70 ℃、平衡时间20 min、循环次数2次的优化条件下,对水中的二氯一溴甲烷进行测定。结果显示,在0.1～10.0 μg/L范围内,二氯一溴甲烷的质量浓度和峰面积呈良好的线性关系,相关系数为0.9991。方法的检出限(S/N=3)为0.03 μg/L,定量限(S/N=10)为0.1 μg/L,回收率为83.1%～111.3%,相对标准偏差为1.7%～5.2%(n=6)。将该方法应用于水中二氯一溴甲烷的定性定量分析,效果良好。     

Gas chromatography and gas chromatography/mass spectrometry for the characterization of complex mixtures of large oligosaccharides

High temperature gas chromatography and gas chromatography/mass spectrometry are used in the characterization of complex natural mixtures of permethylated oligosaccharides released from proteins or lipids. The high resolution allows separation of isomeric compounds and the mass range extends to oligosac-charides around molecular mass 2000 daltons or 10 sugar residues for isomalto-oligosaccharides. The mass spectra of permethylated oligosaccharide alditols from mucin glycopeptides are very informative and the approach allows a simple and rapid characterization of these complex components.     

Discovery of mass spectral characteristics and automatic identification of wax esters from gas chromatography mass spectrometry data

The mass spectral characteristics of wax esters were systemically summarized and interpreted through data mining of their standard mass spectra taken from NIST standard mass spectral library. Combining with the rules of retention indices described in the previous study, an automatic system was subsequently developed to identify the structural information for wax esters from GC/MS data. After tested and illustrated by both simulated and real GC/MS data, the results indicate that this system could identify wax esters except the polyunsaturated ones and the mass spectral characteristics are useful and effective information for identification of wax esters.     

气质联用仪法测定奶粉中多环芳烃

研究了奶粉中多环芳烃的气相色谱/质谱(GC/MS)测定方法. 样品经甲醇-KOH皂化后用甲苯提取, 提取液经微孔滤膜过滤后用气相色谱质谱仪测定其含量, 外标法定量. 结果16种PAHs的回收率范围为92.0%～106%;RSD为2.2%～4.7%. 方法能同时分离16种PAHs, 适合于奶粉中多环芳烃的分析测定.     

Determination of hydroxy-PCBs in urine by gas chromatography/mass spectrometry with solid-phase extraction and derivatization

A sensitive derivatization and extraction method is proposed for the determination of hydroxy-PCBs in urine. Phenolic hydroxyl groups of PCBs were allowed to react with five different reagents such as iodomethane, iodoethane, iodopropane, BSTFA and MTBSTFA. Propylated products at 100 °C for 30 min showed the best sensitivity with mass selective detector. Extraction recoveries and relative standard deviations of hydroxy-PCBs by SPE using C2 column were in the range of 78.0-112.3% and 2.5-9.6%, respectively. Instrumental detection limits for derivatized hydroxy-PCBs were in the range of 1-2 pg and were 10-1000 times more sensitive than those of non-derivatized hydroxy-PCBs. The correlation coefficients of the linear regression curves exceed 0.99, and the intra- and inter-day precisions were evaluated by RSDs within 10% at the concentrations of 0.4 and 4.0 ng/mL.     

Analysis of cholesterol oxidation products by Fast gas chromatography/mass spectrometry

The aim of the present study was to set‐up a Fast gas chromatography/mass spectrometry method for the analysis of cholesterol oxidation products (COPs). A silylated mixture of seven oxysterol standards was injected into a Fast GC/MS system. A capillary GC column (10 m×0.1 mm internal diameter×0.1 μm film thickness) coated with 95% dimethyl‐ and 5% diphenyl‐polysiloxane, was used. The method gave a fast (total analysis time=3.5 min) and satisfactory resolution (R>1.2) of the COPs standards, with a good repeatability and sensitivity, similar to those of conventional GC/MS; recoveries were tested on mice liver. Fast GC/MS method suitability for COPs analysis in food was also tested on an oxidized sardine fillet, which had been previously saponified and purified by NH₂ solid‐phase extraction (SPE); a good repeatability and sensitivity was also obtained. The analytical performance of the Fast GC/MS method for the determination of COPs, together with the consequent significant reduction of the analysis time and consumables, demonstrates that Fast GC/MS represents a valid alternative to conventional GC/MS and evinces the great potential of such an analytical technique, which could be applied for both food and biological samples.     

Determination of ligustilide in rat blood and tissues by capillary gas chromatography/mass spectrometry

A gas chromatography/mass spectrometry (GC/MS) method was developed to study the pharmacokinetics of ligustilide following oral administration to rats. The method was used for the analysis of samples taken from rats. Biological samples were prepared by liquid-liquid extraction (LLE) using an n-hexane-ether (2:1) solvent mixture for a sample clean-up step and analyzed by GC/MS with a quadrupole MS detector in selected ion monitoring mode (m/z 190). The calibration curves were linear over the concentration range 0.172-8.60 microg/mL (r > 0.99) for blood samples and a different range (r > 0.99) for different tissue samples. The limit of detection (LOD) was 1.0 ng/mL or 1.0 ng/g (three times the signal-noise ratio). Within- and between-day precision expressed as the relative standard deviation (RSD) for the method was 1.58-3.88 and 2.99-4.91%, respectively. The recovery for all samples was >80%, except for liver samples (>70%). The main pharmacokinetic parameters obtained were: T(max) = 0.65 +/- 0.07 h, C(max) = 1.5 +/- 0.2 microg/mL, AUC = 34 +/- 6 h microg/mL and K(a) = 3.5 +/- 0.6/h. The experimental results showed that ligustilide was easily absorbed, but its elimination was slow, from 3 to 12 h after oral administration. The concentrations of ligustilide in rat cerebellum, cerebrum, spleen and kidney were higher than those in other organs.     

固相膜萃取与GC/MS联用测定地下水中痕量半挥发性有机物的野外采样方法研究

C18固相萃取膜适宜处理大体积地下水样现场采样而且易于运输、贮存。利用C18固相膜萃取以及GC／MS联用的方法对地下水中痕量半挥发性有机污染物进行了萃取以及定性、定量分析。优化了固相膜萃取的地下水采样量和浓缩体积。有机氯农药和多环芳烃的平均回收率分别为85％～110．1％、90．3％～115．1％；方法检出限达到10^-9g／L；相对标准偏差均小于15％。本方法用于北京地区地下水中的有机污染物分析，并给出地下水样C18固相膜萃取的GC／MS测定结果。     

A low thermal mass fast gas chromatograph and its implementation in fast gas chromatography mass spectrometry with supersonic molecular beams

A new type of low thermal mass (LTM) fast gas chromatograph (GC) was designed and operated in combination with gas chromatography mass spectrometry (GC-MS) with supersonic molecular beams (SMB), including GC-MS-MS with SMB, thereby providing a novel combination with unique capabilities. The LTM fast GC is based on a short capillary column inserted inside a stainless steel tube that is resistively heated. It is located and mounted outside the standard GC oven on its available top detector port, while the capillary column is connected as usual to the standard GC injector and supersonic molecular beam interface transfer line. This new type of fast GC-MS with SMB enables less than 1 min full range temperature programming and cooling down analysis cycle time. The operation of the fast GC-MS with SMB was explored and 1 min full analysis cycle time of a mixture of 16 hydrocarbons in the C(10)H(22) up to C(44)H(90) range was achieved. The use of 35 mL/min high column flow rate enabled the elution of C(44)H(90) in less than 45 s while the SMB interface enabled splitless acceptance of this high flow rate and the provision of dominant molecular ions. A novel compound 9-benzylazidanthracene was analyzed for its purity and a synthetic chemistry process was monitored for the optimization of the chemical reaction yield. Biodiesel was analyzed in jet fuel (by both GC-MS and GC-MS-MS) in under 1 min as 5 ppm fatty acid methyl esters. Authentic iprodion and cypermethrin pesticides were analyzed in grapes extract in both full scan mode and fast GC-MS-MS mode in under 1 min cycle time and explosive mixture including TATP, TNT and RDX was analyzed in under 1 min combined with exhibiting dominant molecular ion for TATP. Fast GC-MS with SMB is based on trading GC separation for speed of analysis while enhancing the separation power of the MS via the enhancement of the molecular ion in the electron ionization of cold molecules in the SMB. This paper further discusses several features of fast GC and fast GC-MS and the various trade-offs involved in having powerful and practical fast GC-MS.     

凝胶渗透色谱净化-气质联用法测定土壤中三嗪类除草剂

建立了以超声波提取、凝胶渗透色谱净化(GPC)、HP-5 MS石英毛细管柱分离、E1离子源质谱法测定土壤中13种三嗪类除草剂的多残留检测方法.三嗪类除草剂的添加水平为0.010～0.100 mg/kg时,平均回收率为72.1%～118.3%,相对标准偏差为2.6%～19.8%(n=4);方法的检出限为0.30～2.50μg/kg.     

Identification of certain chemical agents in complex organic solutions by gas chromatography/tandem mass spectrometry

Analytical methods that are used for the detection and identification of chemicals related to the Chemical Weapons Convention in complex organic solutions were developed. A matrix modified by the addition of complex diesel oil background compounds and interferences was used for the development of a gas chromatography-mass spectrometry or gas chromatography-tandem mass spectrometry (GC-MS or GC-MS/MS) method for unambiguous identification of the scheduled chemicals. Co-elution of diethyl N,N-dimethylphosphoramidate and ethyl N,N-dimethylphosphoramidocyanidate, which are not separated by GC, was identified by GC-MS. Although GC-MS can identify the compounds, GC-MS/MS identification has greater accuracy and sensitivity in the case of complex matrixes. Four scheduled chemicals were accurately and selectively identified against numerous interfering substances by GC-MS/MS. The fragmentation chemistry of these compounds using MS/MS analysis was investigated.     

Identification of RP-HPLC peaks of bisphenol F and of bisphenol F diglycidyl ether and its hydrolysis products by thermospray mass spectrometry and gas chromatography/mass spectrometry

Summary The need to determine the migration of toxic unreacted compounds in bisphenol diglycidyl ether epoxy resins prompted us to investigate the HPLC properties of bisphenol F diglycidyl ether and its hydrolysis products in the water-based food simulants 3% (w/v) acetic acid, distilled water and 15% (v/v) ethanol. Peaks were identified by reversed-phase HPLC thermospray mass spectrometry and gas chromatography/mass spectrometry.     

Urinary metabolomic study of systemic lupus erythematosus based on gas chromatography/mass spectrometry

Systemic lupus erythematosus (SLE) is an autoimmune disease with heterogeneous organ and system manifestations. In this study, urinary metabolic alterations related to SLE were investigated by performing gas chromatography/mass spectrometry (GC/MS) based metabolomics and multivariate statistical analysis. Patients with SLE and healthy controls could be clearly differentiated in view of the metabolic abnormity in urine. Among 70 identified endogenous metabolites, 23 metabolites were dramatically increased in SLE patients, which involved in several key metabolic pathways including energy metabolism, nucleotide metabolism, oxidative stress and gut‐microbiome‐derived metabolism. This noninvasive and GC/MS‐based metabolomic technique is a promising and potent strategy for identifying novel biomarkers and understanding pathogenesis of SLE. Copyright © 2016 John Wiley & Sons, Ltd.     

Comprehensive chemical profiling of Guizhi Fuling capsule by the combined use of gas chromatography-mass spectrometry with a deconvolution software and rapid-resolution liquid chromatography quadrupole time-of-flight tandem mass spectrometry

Herbal formulations are complex natural mixtures. Researchers usually tend to focus more on analysis of nonvolatile components but pay less attention to volatile compounds. In this study, an analytical strategy combining two approaches was established for comprehensive analysis of herbal formulations. Guizhi Fuling capsule (GFC), a drug approved by the FDA to enter phase II clinical trial for treatment of primary dysmenorrhea, was taken as a case for analysis. Gas chromatography–mass spectrometry (GC‐MS) with automated mass spectral deconvolution and identification system (AMDIS) led to rapid identification of 48 volatile components including four acetophenones, three fatty acid esters, 13 phenylpropanoids and 19 sesquiterpenes. Most of them were found from Guizhi. The volatile oils of Guizhi have been proved to exhibit many pharmacological activities. This is helpful in understanding the pharmacological mechanism of GFC. Furthermore, AMDIS turned out to be efficient and reliable for analysis of complex herbal formulations. Rapid‐resolution liquid chromatography (RRLC) coupled with electrospray ionization quadrupole time‐of‐flight tandem mass spectrometry (ESI‐Q‐TOF MS/MS) allowed the identification of 70 nonvolatile components including six acetophenones, 12 galloyl glucoses, 31 monoterpene glycosides, three phenols and 12 triterpene acids. Fragmentation behaviors of assigned components, especially triterpene acids, which are hard to identify by low‐resolution MS, were first investigated by TOF MS/MS. Characteristic ions and typical loss of assigned triterpene acids were summarized. Combinatorial use of GC‐MS‐AMDIS and RRLC‐ESI‐Q‐TOF MS/MS could be of great help in global qualitative analysis of GFC, as well as other herbal products. Copyright © 2012 John Wiley & Sons, Ltd.     

Direct analysis of polychlorinated biphenyls in heavily contaminated soils by thermal desorption/gas chromatography/mass spectrometry

A robust analytical method is presented for the direct determination of polychlorinated biphenyls in soil samples by thermal desorption/gas chromatography/mass spectrometry. The method is simple to perform (thermal desorption and analysis are performed in-line employing a limited amount of sample, 2?mg) and eliminates the need for any solvent and time-consuming extraction. The analytical procedure was optimized using a soil sample spiked with Aroclor 1254 and Aroclor 1260 and validated with a certified industrial soil sample for which the concentration of thirteen PCB congeners are known. Limits of detection were sensitive to matrix effects and varied substantially among analytes. The matrix effect resulted in a reduction of the limits of detection by 1.5–10 times. However, it was found that the matrix effect is not due to ion suppression but to the increase of the noise of selected ion monitoring (SIM) traces, indicating that no limitation exists with using a single surrogate standard. By employing a 13C-labelled PCB internal standard, limits of detection in the range of 0.8 to 10?µg?g^?1 of soil were obtained. The obtained experimental results demonstrated that the proposed analytical method can be conveniently applied for screening a large number of heavily contaminated soil samples thus avoiding the employment of harmful solvents and time-consuming extraction procedures.     

Using the tools of chromatography,mass spectrometry,and automated data processing in the detection of arson

The analysis of residual accelerants in fire debris is commonly carried out by a three-step procedure: sample preparation; separation and detection; and data interpretation. Each of these steps can be optimized individually but successful analysis requires that they are compatible with each other. The isolation of residual accelerant from fire debris requires that several methods are used to cover the range of fueis that are commonly used by arsonists. Since almost all incendiary fires are set with petroleum based fuels such as gasoline or heating oil, analysis is targeted toward hydrocarbons. Capillary column gas chromatography on apolar phases is now the overwhelmingly predominant method of separation. Data interpretation is commonly carried out by visual comparison of chromatograms. Fire debris analysis presents some unique challenges that are not often encountered in other fields. The analyte may be present at only trace levels and pyrolysis products from building materials or furnishings may dominate chromatographic patterns. Synthetic polymers may act as precursors to hydrocarbons that compete with substances typically found in petroleum based fuels. Exposure to heat and other environmental factors may also generate severe distortions in the chromatographic profiles of accelerants. Unfortunately, there is no simple solution to these problems. Methods are available to reduce some of the chemical noise introduced by interferences and thus enhance the recognizability of the target substances. Mass spectrometry, in combination with a modern data system, is the most effective approach to filter out unwanted substances. The interpretation of the analytical results is aided by scaling, side-by-side comparison, or stacking of chromatograms. An additional advantage of such computerized systems is the possibility of complete automation of the analysis. In this communication, we look at the interplay of chromatographic resolution, noise reduction by mass spectrometry, and automated data evaluation. Examples from model experiments and from simulated arson samples are presented.     

High resolution gas chromatography/mass spectrometry analysis of the environmental pollutants methylnitronaphthalenes

We report the linear retention indices of the 14 methylnitro-naphthalenes on three high resolution capillary columns and their electron impact mass spectra. The analyses of the methylnitro-naphthalenes in an ambient air sample by gas chromatography/mass spectrometry with multiple ion detection utilizing 5% phenylmethylsilicone, 50% phenylmethylsilicone, and smectic columns are shown.     

New designer drug 1-(3-trifluoromethylphenyl) piperazine (TFMPP): gas chromatography/mass spectrometry and liquid chromatography/mass spectrometry studies on its phase I and II metabolism and on its toxicological detection in rat urine

Studies are described on the phase I and II metabolism and the toxicological analysis of the piperazine-derived designer drug 1-(3-trifluoromethylphenyl)piperazine (TFMPP) in rat urine using gas chromatography/mass spectrometry (GC/MS) and liquid chromatography/mass spectrometry (LC/MS). The identified metabolites indicated that TFMPP was extensively metabolized, mainly by hydroxylation of the aromatic ring and by degradation of the piperazine moiety to N-(3-trifluoromethylphenyl)ethylenediamine, N-(hydroxy-3-trifluoromethylphenyl)ethylenediamine, 3-trifluoromethylaniline, and hydroxy-3-trifluoromethylaniline. Phase II reactions included glucuronidation, sulfatation and acetylation of phase I metabolites. The authors' systematic toxicological analysis (STA) procedure using full-scan GC/MS after acid hydrolysis, liquid-liquid extraction and microwave-assisted acetylation allowed the detection of TFMPP and its above-mentioned metabolites in rat urine after single administration of a dose calculated from the doses commonly taken by drug users. Assuming similar metabolism, the described STA procedure should be suitable for proof of an intake of TFMPP in human urine.