Toxicological analysis of thiamylal in biological materials by gas chromatography/mass spectrometry

A reliable and sensitive method to analyze thiamylal in biological materials was developed, using gas chromatography/mass spectrometry (GC/MS). A quantitative determination was made by use of mass fragmentography with the lower detection limit of 0.01 microgram/g. Thiopental was used as the internal standard. Distribution of the drug in the blood and body tissues of rats was examined. The method was then used to detect thiamylal in tissues from an autopsied patient and concentration of this drug in the body materials was evaluated, from medico-legal aspects.     

苯丙胺类毒品三氟乙酰化气一质联用分析

目的　考查了N甲基双三氟乙酰胺 (MBTFA)衍生化试剂对苯丙胺类毒品的衍生化效果与衍生化条件 ,建立该类毒品三氟乙酰化后的定性定量分析条件。方法　用三氟乙酰化气一质联用分析方法。结果　获得了衍生化产物经气质联用分析后的总离子流色谱图、质谱图及质谱断裂规律 ,以及各种定量参数。结论　经三氟乙酰化后分离效果得到改善 ,且衍生化完全 ,可用于该类毒品的定量分析。     

Determination of clofelin in blood by gas chromatography-mass spectrometry

Gas chromatography--mass spectrometry is proposed for measuring clofelin (clonidine) in cadaveric blood. The method includes liquid-liquid extraction of clonidine from the blood, derivatization with pentafluorobenzyl bromide, and subsequent purification of derivatization products before chromatographic analysis. The range of 0.5-50.0 ng/ml covers therapeutic and lethal concentrations of clonidine in the blood. The method was tried on expert material in Chelyabinsk Regional Bureau of Forensic Medical Expert Evaluations and can be used in forensic chemical and toxicological analysis.     

The analysis of illicit methaqualone containing preparations by gas chromatography-mass spectrometry for forensic purposes

A validated gas chromatographic-mass spectrometric method for quantitative analysis of methaqualone (MTQ) in illicit preparations is reported. The method proved to have a coefficient of variation of below 5%. Four batches of seized tablets, two pairs with similar imprints, were analyzed. It was found that the average MTQ concentration in all four batches of tablets differed significantly (p = 0.01) rendering it impossible to conclude that, on the basis of MTQ concentration alone, the batches with a similar logo originated from the same manufacturer or manufacturing batch. Conversely, it can be said that in this case, the four batches originated from either different clandestine laboratories or manufacturing batches.     

血中精神药物的气相色谱-质谱分析

目的建立人血中精神药物的GC-MS测定方法。方法样品在pH12条件下用乙醚萃取,SKF_525A为内标。以DB-5MS石英毛细管柱、EI源、不分流进样测定人血中四种精神药物。结果人血中四种精神药物与内标物分离良好,血药浓度在0.2-1.0μg,／ml范围内呈线性关系,R2≥0.9728,最低检出限为0.01μg(S／N≥3),血中精神药物的最低检出浓度为0.05μg／ml(S／N≥3),提取率72.5％～89.3％,RSD≤5.17％。四种精神药物日内差RSD≤3.7％(n=5)。结论本法可用于精神药物的血药浓度监测。     

Urinary cannabinoid analysis: comparison of four immunoassays with gas chromatography-mass spectrometry

Eight-eight urine samples were analysed by the EMIT d.a.u. Cannabinoid 20 ng homogeneous enzyme immunoassay, the DPC cannabinoid radioimmunoassay, two in-house cannabinoid radioimmunoassays and a gas chromatography-mass spectrometry method for 11-nor-9-carboxy-delta 9-tetrahydrocannabinol. There was good qualitative agreement between the methods with few discrepancies in the borderline region.     

固相微萃取-气相色谱质谱法测定血浆中的氯氮平浓度

目的建立固相微萃取-气相色谱质谱法测定人血浆中氯氮平浓度的方法。方法以固相微萃取法提取血浆中的氯氮平,萃取头为100μm聚二甲基硅氧烷,洛沙平作内标,用气相色谱质谱选择离子法进行检测。结果本文建立的方法在5~2000 ng/ml浓度范围内呈线性关系,检测限为0.1 ng/ml(信噪比>3),低、中、高浓度(100、500、1000 ng/ml)平均相对回收率分别为98.6%、94.6%和94.6%,日内、日间RSD分别小于7.4%和7.1%。结论本文建立的固相微萃取-气相色谱质谱法灵敏度高、准确度好、操作简便,适用于氯氮平急性中毒案件的检测。     

Differentiation of ballpoint pen inks by thermodesorption and gas chromatography-mass spectrometry

Differentiation and classification of ink entries with dated samples of a reference collection are important aspects in the examination of questioned documents. Classification of writing inks is presently achieved by analysis of dyes and colorants contained in the ink. This technique has its limitations in newly developed ink formulations with identical dye composition but differing in their solvents and binder resins. This paper introduces a method for the determination of solvents and binder resins of an ink sample directly from paper without sample preparation. This aim is accomplished by thermodesorption of the sample followed by gas chromatography/mass spectroscopy. The method was tested on numerous samples of ballpoint pen inks, which were subsequently grouped into several solvent and resin subgroups. A case study shows the applicability of the newly developed method.     

The determination of clozapine in blood and urine by gas chromatography-mass spectrometry]

A method for measuring closapine in the blood and urine by gas chromatography-mass spectrometry as a trifluoroacetic derivative is proposed. The threshold level for closapine detection is 25 ng/ml in the blood and 30 ng/ml in the urine. Calibration curves are linear in the range 0.025-5 mcg/ml for the blood and 0.03-50 mcg/ml for the urine. The method can be used in forensic chemical and clinical toxicological analysis.     

Impurity profiling of ecstasy tablets seized in Hong Kong by gas chromatography-mass spectrometry

In Hong Kong, ecstasy tablets are more commonly known as "Fing Tau Yuen", literally meaning "Shake Head Pills". The tablets contain mainly amphetamine-type stimulants (ATS) including 3,4-methylenedioxymethamphetamine (MDMA), 3,4-methylenedioxyamphetamine (MDA), methamphetamine (MA) and/or ketamine. Adulterant such as caffeine was also detected in the tablets. This paper reports a study on the impurity profiles of ecstasy tablets from 89 seizures in Hong Kong from 2002 to early 2004. Tablet samples were extracted by diethyl ether under alkaline condition and then analyzed by gas GC-MS. The chromatograms obtained were compared. A total of 19 identified impurities were selected as markers for impurity profiling. They are different precursors, intermediates and by-products. The data matrices were examined by hierarchical cluster analysis (HCA), and then the ecstasy tablets were classified into different groups. Cluster analysis of ecstasy tablets is shown to be capable of providing intelligence on clandestine laboratory networks.     

1,8-二氨基萘衍生化GC/MS法测定尿中的亚硝酸盐含量

目的建立快速准确测定尿液中的亚硝酸盐含量的方法。方法采用1,8-二氨基萘(1,8-DAN)衍生化气相色谱-质谱(GC/MS)法进行分析,并对实验参数如p H值、衍生化温度和时间进行了优化。结果本方法测定尿液中的亚硝酸盐含量的线性范围0.01~20μg/m L,相关系数R~2=0.998 4,检测限为0.005μg/m L,日内精密度(n=4)为3.49%~4.31%;日间精密度(n=5)为4.18%~5.76%,回收率为88.37%~116.0%,实验耗时30min。结论该方法可直接在尿液中进行衍生化GC/MS分析,具有耗时更短、检测限更低、回收率和精密度高的优点,操作简便快捷,在法医毒物分析中具有实际应用价值。     

Determination of elemental sulfur in explosives and explosive residues by gas chromatography-mass spectrometry

A new method for the positive identification of elemental sulfur in explosives and explosive residues is developed. Following a carbon disulfide wash of explosives or explosive residues, a sample of the extracted material is injected onto a gas chromatography (GC) column, then analyzed via mass-selective (MS) detection. A positive identification of elemental sulfur is based on both retention time and fragmentation pattern. The GC-MS method is demonstrated to be useful in detecting and positively identifying elemental sulfur from both burned and unburned explosive mixtures. With a detection limit of 2.5 ng (2.5 x 10(-9) grams) of elemental sulfur on the column, it is shown to be 400 times more sensitive than the presumptive chemical color test that is currently the method employed for detection of small amounts of sulfur.     

Comparison of motor oils using high-temperature gas chromatography-mass spectrometry

The analysis of motor oils has wide applications in the forensic science field from comparing lubricants transferred between an automobile and a victim or crime scene to differentiating the compositions of plastic explosives. In this study, 40 unused motor oils were analyzed and compared by high-temperature gas chromatography-mass spectrometry to determine the potential for oil individualization. Oil samples were also collected from the crankcase dipsticks of 30 cars. Twenty-six of these oils could be differentiated from each other based on visual comparisons of the unresolved envelope (baseline rise due to incomplete separation) and the resolved hydrocarbons in the raw total ion chromatograms (TICs) and smoothed TIC data. Four of these oils were analyzed as unknowns and were correctly related to the corresponding vehicle. The use of extracted ion profiles (EIPs) was explored as a means to further discriminate between the indistinct samples based on the polycyclic aromatic hydrocarbon (PAH) content. The research discussed in this paper demonstrated that differentiation of motor oils was possible by examining the TIC, smoothed TIC, and EIP data.     

固相萃取-气相色谱-质谱法检验人血浆中的右美托咪定

目的采用固相萃取结合气相色谱-质谱法(SPE-GC/MS)检验人血浆中盐酸右美托咪定。方法采用SPE提取血浆,用GC-MS/MS方法测定。结果盐酸右美托咪定在0.2μg/m L~5.0μg/m L范围内与峰面积呈现良好的线性关系(r2=0.999 1),检出限为20.0ng/m L,回收率为86.1%~91.5%,日内日间精密度均小于7.86%。结论本方法操作简单,结果准确,可以作为测定人血浆中右美托咪定的方法。     

Detection of the calcium antagonist nicardipine and its metabolites by gas chromatography-mass spectrometry

An 89-year-old male patient, hospitalized with Parkinson's syndrome, suddenly died shortly after an intravenous drug injection. The conditions indicated that an overdose of nicardipine (1.3 mg/(mlkg)) may be given to the patient. At the autopsy, no pathological changes were noted. With a capillary gas chromatograph with mass spectrometer (GC-MS), nicardipine (4.97 microg/ml) and its pyridine metabolite (M-5, 5.0 microg/ml) were detected in the heart blood of the deceased. This result indicated that an overdose of intravenous nicardipine caused a sudden death of a patient in a poor condition.