双毛细管柱双检测器气相色谱法检测常见毒物

法庭毒物检验鉴定主要依据气相色谱仪和气-质联用仪,气相色谱仪对毒物定性是以药物的Rt值来判定,但由于GC法鉴别能力较差,许多药物之间Rt值相近,很难判别,为此我们利用VSOS将单柱单检测器改造成双毛细管柱双检测器定性分析。样品进样后经VSOS同时进入两根不同极性的毛细管柱,至两个不同的检测器,根据样品在不同极性色谱柱中的保留时间和不同检测器对同一毒物的选择性响应的差异,对毒物进行定性分析,该方法可使GC鉴别能力获得很大提高。1仪器与方法1.1仪器、试剂Varian3800气相色谱仪,配氢火焰离子检测器(FID)和氮磷检测器(TSD);DM…     

定量数据关联二级全扫描与选择反应监测在常见毒物检测中的应用

目的建立快速、准确,可同时进行定性定量的常见毒物的筛选检测方法。方法用Thermo TXQQuantum XLS气相色谱—三重四级杆质谱仪对57种常见毒物及内标惊醒检测。结果得到了57种常见毒物及内标的选择反应检测信息,并且农药鼠药检测限可达到0.1ng/μL水平,药品检测限达27pg/μL水平,毒品检测限达0.4ng/μL水平。结论该方法具有快速、灵敏、准确的优点,可在一次扫描中完成样品的定性定量分析检测。     

GC/MS/AMDIS在法医毒物分析中的应用

目的探索自动质谱去卷积定性系统(AMDIS)在法医毒物分析中的应用。方法利用自动质谱去卷积定性系统(AMDIS)、全扫描离子模式(FIM)和选择离子监测技术(SIM)对农药、毒品、安眠镇静类药等常见毒物进行检索分析,比较三种检索方式对不同质量浓度(40.0、4.0、0.4mg/L)毒物的检验结果。结果AMDIS与SIM具有相近的灵敏度,可以将GC/MS全扫描文件去卷积处理,解决杂质干扰问题,准确对目标化合物进行定性;AMDIS可以自动识别重叠的色谱峰并将其与目标谱库进行匹配,为重叠峰的定性提供了直观的鉴别依据。结论AMDIS检索自动快速,适用于GC/MS法快速鉴定毒物。     

谈“双专业”的利弊及可行性方案

<正> “双专业”,即大学生入学一年后根据自己的能力选择自己喜读的两个专业,把两个专业的课程修满学分达到要求后得到两个专业的毕业证书。北京大学法律学系从1994年开始实行“双专业”教育。通过一年多的实践,其利弊不同程度地显示出来,就此,谈谈我对双专业实施问题的见解和看法。 实行双专业,它是对传统高等教育模式的一种补充和完善,需要在实践中不断进行检验。法律系实行双专业在北大教学改革中实属首创,其有利之处可归纳为以下三点:     

双差异分离法对混合斑快速检验的初探

目的建立强奸案中混合斑的分离检验新方法,并评估其应用价值。方法采用双差异分离法对人工制备的3个不同浓度的模拟混合斑样本及相应滤膜进行分离提取,对所得DNA进行定量分析和STR分型检验。结果不同浓度的3个样本经孔径为10μm尼龙网格膜两次离心过膜后精子细胞损耗率均小于3%,同时3个样本沉淀均检出完整单一的男性STR分型。结论该双差异分离法所用滤膜对精子细胞DNA的损耗极少并且具有稳定性;该方法用于精阴混合斑的分离检验,具有高分离效率,装置简单,操作便捷,成本低廉等优势,为性侵案中混合斑的分离检验提供了一种新思路。     

刺激性毒物西阿尔（CR）的检验

目的简要介绍刺激性毒物西阿尔的物理、化学性质及检验方法;方法使用直接提取法对常见检材进行提取,使用TLC、GC/MS方法对其进行定性分析,以西阿尔在不同展开系统下的Rf值和特征质谱图作为定性依据;结果可快速准确的对西阿尔进行定性分析;结论该方法简便,易行,准确,可靠,可用于案件检验。     

气质联用仪自动筛选常见毒物的应用研究

目的建立快速、灵敏的常见毒物的质谱自动筛选检测方法。方法建立常见毒物的质谱用户库，优化分离条件，优化质谱数据的自动分析参数，进行标样和样品分析。结果建立了含1306种常见毒物的质谱用户库；建立了自动筛选方法；得到了150种常见毒物的保留时间和检测限。结论建立的方法具有快速、灵敏、准确的优点，完全可替代繁杂的质谱检索手工操作。     

LC-MS/MS-MRM筛选血液中22种有毒生物碱成分

目的建立液相色谱-串联质谱法对血液中的22种常见有毒生物碱成分进行筛选分析。方法血液以丁丙诺菲为内标经液液提取后,用液相色谱-串联质谱仪以电喷雾电离(ESI )、多反应监测(MRM)方式进行分析。结果以化合物的保留时间、两对母离子/子离子对定性,最低检出限为0.1～20ng/mL。结论该方法选择性佳、灵敏度高,适用于法医毒物分析和临床毒物分析中有毒生物碱的分析。     

用分时选择离子质谱法一次检测多种药物

目的建立一种能避免生物样品中杂质的干扰,一次排查多种药、毒物,准确、灵敏度高的检验方法。方法应用分时选择离子质谱法,对常见毒物进行检验研究。结果在样品经简单净化处理的情况下,以分时选择离子质谱法检测,一次检测多个毒物(最多32个),定性、定量准确,灵敏度50～100ng/ml,经与全扫描质谱法进行比较,灵敏度提高2～3个数量级。结论该方法能有效提高排查毒物检测灵敏度,适用于常见毒物的排查检验。     

固相萃取-色谱质谱技术在毒物筛查中的应用进展

固相萃取是近年发展起来的一种样品前处理技术,主要用于样品的分离和富集,能够将生物检材中的目标待测物有效的与杂质组分分离,具有较高的回收率,其样品预处理过程简单,操作便捷。在法庭科学领域,可根据生物检材,如生物体液、组织、毛发等基质的性质,选择相应的固相萃取方法;同时亦可根据目标待测物,如目标待测物的酸碱性,选用不同的固相萃取方法。色谱法是一种分离和分析方法,它利用不同物质在不同相态的选择性分配,使混合物中的不同组分根据其性质不同而分离。质谱法在分析中可提供丰富的结构信息。固相萃取-色谱质谱联用技术集固相萃取与色谱质谱检测技术优点于一体,可实现对复杂基质中的特定毒物与非特定毒物进行高效萃取、净化与检测,具有检材消耗少、检测速度快、灵敏度高等特点,已被广泛应用于环境监测、药物分析、法庭科学领域等,成为当前毒物筛查的重要手段,具有选择性好、灵敏度高、基质效应低等特点,且易实现在线分析,特别适用于法庭毒物分析中单一毒物或多种毒物的筛查。本文综述了固相萃取-色谱质谱联用技术在法庭科学毒物毒品分析中的应用进展,以供同行参考。     

红外光谱在毒药物检验中的应用

目的　建立毒药物检验的红外光谱测定方法。　方法　用液液萃取法提取检材中的安眠药、精神药品、农药、杀鼠剂和无机毒物 ,然后应用红外光谱法进行定性分析。　结果　常见毒药物均有其特征红外吸收峰 ,通过其特征吸收峰可以区分不同毒药物。　结论红外光谱法快速、准确 ,适用于干扰较轻检材中毒药物的定性分析。     

An evaluation of fused silica capillary columns for the screening of basic drugs in postmortem blood: qualitative and quantitative analysis

Fused silica capillary columns (Durabond) have been evaluated for the screening of more than 100 basic drugs in postmortem blood samples. The combination of these columns, nitrogen-phosphorus detectors, and SKF-525A (internal standard) allows for the simultaneous screening and quantitation of several basic drugs such as amphetamines, amitriptyline, and codeine. Approximately 2000 blood samples have been analyzed by this procedure. The use of capillary columns results in excellent baseline stability and this, together with an autosampler and data system, enables unattended overnight operation. "Double peaking" associated with splitless injection can be a problem as can sensitivity for some of the polar drugs; however, with the extraction procedure described and the equipment used, the screening of blood for basic drugs is improved when compared with packed column technology.     

Simple and simultaneous quantification of cyanide,ethanol, and 1-propanol in blood by headspace GC–MS/NPD with Deans switch dual detector system

Cyanide is a powerful and rapidly acting poison. In Japan, cyanide poisoning is rare, and regular cyanide testing can be costly and time consuming. In contrast, alcohol analysis is routinely performed in most forensic laboratories. In this study, we attempted to develop a method for the simultaneous quantification of cyanide and alcohols in blood using headspace gas chromatography (HS–GC). As nitrogen-phosphorus detection (NPD) is more sensitive to hydrogen cyanide than mass spectrometry (MS), a Deans switch was used to switch the detectors during a single run. The separation provided by three analytical columns, PoraBOND Q, CP-Sil 5 CB, and HP-INNOWax, was investigated, and PoraBOND Q was selected. The use of HS–GC–MS/NPD with a Deans switch enabled the simple and simultaneous quantification of cyanide, ethanol, and 1-propanol. Eighteen other volatile compounds were detected in the SIM/scan mode of the MS.     

Forensic analysis of commercial petroleum products using selective fluorescence quenching.

A novel method for the forensic analysis of commercial petroleum products is presented. In this approach, the petroleum sample is extracted with nitromethane and then separated by capillary liquid chromatography with laser-induced fluorescence detection. The addition of selective fluorescence quenching agents allows the sample to be profiled by the distribution of alternant and nonalternant polycyclic aromatic hydrocarbons (PAHs). In preliminary studies, the quenching behavior of nitromethane and diisopropylamine was established by using a standard mixture of sixteen PAHs ranging in size from two to six aromatic rings. Subsequent examination of new and used motor oil demonstrated that characteristic differences arise in the PAH content, which may allow for the unique identification of oil from a particular engine or vehicle. In addition, three brands of petrolatum jelly were successfully distinguished. Although a number of alternant alkylated and heterocyclic PAHs were found in all petrolatum samples, there were significant differences in the relative concentrations of alternant as well as nonalternant PAHs. This allowed for clear differentiation of the samples through qualitative inspection of their chromatograms as well as quantitative statistical correlation techniques.     

Preparation and characterization of micro-bore wall-coated open-tubular capillaries with low phase ratios for fast-gas chromatography–mass spectrometry: Application to ignitable liquids and fire debris

Fast Gas Chromatography (GC) allows for analysis times that are a fraction of those seen in traditional capillary GC. Key modifications in fast GC include using narrow, highly efficient columns that can resolve mixtures using a shorter column length. Hence, a typical fast GC column has an inner diameter of 100–180 μm. However, to maintain phase ratios that are consistent with typical GC columns, the film thickness of fast GC stationary phases are also low (e.g., 0.1–0.18 μm). Unfortunately, decreased film thickness leads to columns with very low sample capacity and asymmetric peaks for analytes that are not sufficiently dilute. This paper describes micro-bore (50 μm i.d.) capillary columns with thick films (1.25 μm), and low phase ratios (10). These columns have greater sample capacity yet also achieve minimum plate heights as low as 110 μm. Hence, separation efficiency is much higher than would be obtained using standard GC columns. The capillary columns were prepared in-house using a simple static-coating procedure and their plate counts were determined under isothermal conditions. The columns were then evaluated using temperature programming for fast GC–MS analysis of ignitable liquids and their residues on fire debris exemplars. Temperature ramps of up to 75 °C min^?1 could be used and separations of ignitable liquids such as gasoline, E85 fuel, and lighter fluid (a medium petroleum distillate) were complete within 3 min. Lastly, simulated fire debris consisting of ignitable liquids burned on carpeting were extracted using passive headspace absorption-elution and the residues successfully classified.     

Analyse von heroinproben mit der Kapillargaschromatographie. Vergleich von Glaskapillartrennsäule und gepackter Säule

In forensic examination of illicit heroin samples high-resolution capillary gas chromatography is compared with gas chromatography with packed columns. Separation efficiency, reproducibility of qualitative and quantitative determinations and stability of the columns are examined.A practical method with silylation of the samples is presented which allows safe identification and quantification of many various compounds contained in illicit heroin samples. The gas chromatographic data of 35 substances (opium alkaloids and synthetic derivatives, adulterants and diluents) are listed. The method also allows the quantification of morphine, opium, and cocaine samples.     

Elemental analysis of glass fragments by ICP-MS as evidence of association: analysis of a case

Inductively coupled plasma mass spectrometry (ICP-MS) was used to analyze glass evidence from a case in which a person broke a window in each of 15 vehicles in a parking lot in order to gain entry into the vehicles. The results of the analysis by traditional methods, which measure the properties of color, thickness, density, and refractive index, are also reported. A total of 15 known samples representing the windows on the cars and 42 questioned glass fragments recovered from the suspect and the police vehicle where the suspect was sitting were submitted for analysis. Density comparisons separated one of the known samples into three samples, increasing the number of known samples from 15 to 17. The concentrations of 16 elements were measured for all but three of the samples using an external calibration ICP-MS method with internal standardization. Color assessment (non-instrumental) separated the 17 known samples into two groups, and refractive index measurements resulted in six groups when the Emmons double variation method was used and ten groups when the Glass Refractive Index Measurement 2 (GRIM2) system was used. Elemental analysis, by itself, differentiated all of the known samples from each other and associated four of the known sample fragments with several of the questioned sample fragments. The informing power of RI, density, and elemental analysis comparisons is evaluated and a summary of the case results is reported.     

尸体脏器中几种镇静药物气相色谱/质谱测定的研究

本文应用气相色谱/质谱(GC/MS)技术,研究了尸体脏器中五种巴比妥酸盐、导眠能、苯妥英的定性和定量分析方法。应用SE-54毛细柱找到了良好分离条件。以安眠酮作内标,建立了定量分析程序。应用这个方法,可在1小时内完成定性分析,检测限为5ng;定量分析的准确度和精密度均为±10％。     

Rapid isolation of some antiepileptic hydantoins and their analogues with Sep-Pak C18 cartridges and capillary gas chromatography with splitless injection

A simple and rapid method for isolation of seven antiepileptics (2 hydantoin, 2 oxazolidin, and 3 suximide derivatives) from urine and plasma is presented. Urine and plasma (1 ml) samples containing seven antiepileptics were mixed with distilled water (4 ml), and the sample solution was poured into a pretreated Sep-Pak C18 cartridge; this was washed with water and chloroform/methanol was passed through it to elute the antiepileptics. The eluate was mixed with isoamyl acetate and evaporated under a stream of N2. The drugs were detected by gas chromatography with fused silica capillary columns, splitless injection and flame ionization detection. Separation of the seven antiepileptics from each other and from impurities was satisfactory with the use of an SPB-1 capillary column. The detection limit for the seven antiepileptics with the present method was 0.1-1.0 microgram/ml urine or plasma. The recovery of the drugs from urine and plasma was more than 70% and 50%, respectively.     

毛细管电泳技术分析炸药残留物中无机离子

目的　建立炸药残留物中无机离子的毛细管电泳检测方法。方法　运用缓冲溶液使无机离子在毛细管电泳中达到分离 ,采用紫外间接检测法分析。结果　该方法可从爆炸残留物中准确检测出无机阴离子 (Cl- 、SO2 - 4、NO- 2 、NO- 3、ClO- 3和ClO- 4离子 )和无机阳离子 (NH 4、K 、Na 和Mg2 离子 )。结论　操作方法简便快捷 ,检材用量少 ,检测极限可达ng/ml级 ,分析结果满意