GPC-GC/MS法分析血中20种安眠镇静药物

目的研究建立液液提取-在线GPC-GC/MS同时分析血中巴比妥类、吩噻嗪类、苯并二氮杂卓类、三环类和其他安眠精神类药物的方法。方法血样加入内标SKF525A,加β-葡萄糖酸苷酶水解后用乙腈沉淀蛋白浸取药物,加无水硫酸镁脱水,提取液浓缩至干后用GPC流动相定容,在线GPC净化,大体积进样,GC-MS分析。结果选择总离子监测模式,血中20种安眠镇静药物提取率在80.2%～99.3%之间,检出限小于21.6ng/mL;在0.1～10μg/mL浓度范围内工作曲线的线性关系良好。结论方法可用于安眠镇静类药物误服中毒者和刑事案件中毒者血样的分析。     

A Comparison of Enhancement Techniques for Footwear Impressions on Dark and Patterned Fabrics,

The use of chemical enhancement techniques on porous substrates, such as fabrics, poses several challenges predominantly due to the occurrence of background staining and diffusion as well as visualization difficulties. A range of readily available chemical and lighting techniques were utilized to enhance footwear impressions made in blood, soil, and urine on dark and patterned fabrics. Footwear impressions were all prepared at a set force using a specifically built footwear rig. In most cases, results demonstrated that fluorescent chemical techniques were required for visualization as nonfluorescent techniques provided little or no contrast with the background. Occasionally, this contrast was improved by oblique lighting. Successful results were obtained for the enhancement of footwear impressions in blood; however, the enhancement of footwear impressions in urine and soil on dark and patterned fabrics was much more limited. The results demonstrate that visualization and fluorescent enhancement on porous substrates such as fabrics is possible.     

A Review of Alcohol‐Impaired Driving: The Role of Blood Alcohol Concentration and Complexity of the Driving Task

The operation of a motor vehicle requires the integrity of sensory, motor, and intellectual faculties. Impairment of these faculties following the consumption of alcohol has been studied extensively through laboratory, closed‐course and on‐road driving, and epidemiological studies. The scientific literature was reviewed critically, with a focus on low‐to‐moderate blood alcohol concentrations (BAC ≤ 0.100%), to identify the most reliable determinants of alcohol‐impaired driving. Variables such as age, gender, driving skill, and tolerance were shown to have limited impact on impairment. It was concluded the most relevant variables are BAC and complexity of the driving task. The scientific literature provides a high degree of confidence to support the conclusion that a BAC of 0.050% impairs faculties required in the operation of a motor vehicle. Whether impairment is apparent depends upon the complexity of the driving task, which applies to both study design and actual driving.     

GC/MS衍生化法检测血中4-溴-2,5-二甲氧基苯乙胺

目的建立人体全血中4-溴-2,5-二甲氧基苯乙胺的衍生化GC/MS分析方法。方法血液样品经去离子水稀释4倍,8000r/min高速离心20min后,加入Na H2PO4缓冲溶液(p H值为6.0)2m L,混匀。将上述混合液加入用甲醇、Na H2PO4缓冲溶液(p H值为6.0)活化的Bond Elut Centify?固相萃取柱后,依次采用1.0M乙酸溶液、去离子水、甲醇、二氯甲烷/异丙醇/氨水(78/20/2,V/V/V)混合洗脱液进行提取、分离、净化处理,40℃空气流下挥干,三氟乙酸酐衍生化,GC/MS检测4-溴-2,5-二甲氧基苯乙胺和4-苯基丁胺衍生物。采用标准品衍生化产物的标准质谱图定性分析,选择m/z 242(4-溴-2,5-二甲氧基苯乙胺)、m/z 91(4-苯基丁胺)作为定量离子进行定量分析。结果血液中4-溴-2,5-二甲氧基苯乙胺的最低检出限为6ng/m L,在0.02~10μg/m L浓度范围内,线性关系良好(=0.9993),日内精密度和日间精密度均小于10%,平均提取回收率约为69%。结论该方法操作简便、灵敏度高,适用于全血中4-溴-2,5-二甲氧基苯乙胺检测。     

气相色谱-串联质谱法分析尿和血中除草剂百草枯

目的建立尿和血中百草枯的离子交换固相萃取-气相色谱-串联质谱分析方法。方法尿样加内标乙基百草枯,用732阳离子交换树脂提取;血样加内标乙基百草枯,用三氯乙酸凝聚蛋白质后取上清液用732阳离子交换树脂提取。提取物用硼氢化钠在水溶液中碱性条件下还原,还原物用有机溶剂提取进行气相色谱-串联质谱法分析。结果尿和血中百草枯的提取率分别为76％和74％,检测限分别为2ng／mL和10ng／mL,尿添加百草枯100ng／mL和血添加百草枯500ng／mL水平的回收率分别为99．6±5．6％和99．3±7．6％（Mean±CV）。结论本文建立的分析方法灵敏度高,能够满足中毒致死案件检验及临床毒物检验的需要。     

不同温度下血样中毒鼠强的稳定性

目的探讨不同保存温度下血样中毒鼠强的稳定性。方法配制毒鼠强质量浓度为0.5μg/mL的血液样品,分别置于45℃、25℃和4℃环境中保存,在配制当天及存放3、12、18和39d用气相色谱-质谱联用法测定其质量浓度,运用SPSS统计软件对结果进行统计分析。结果45℃、25℃下血样存放3d毒鼠强质量浓度基本不变,存放4～12d毒鼠强质量浓度有明显下降,存放12d后毒鼠强质量浓度缓慢下降;4℃下血样存放12d毒鼠强质量浓度基本不变,存放13～18d毒鼠强质量浓度有明显下降,存放18d后毒鼠强样品质量浓度缓慢下降。结论血样中毒鼠强质量浓度在最初的3d内稳定,此后浓度下降。保存温度对血样中毒鼠强质量浓度有影响。     

Elevated morphine concentrations determined during infant death investigations: artifacts of withdrawal of care

Abstract:  Three cases are reported of elevated postmortem blood morphine concentrations (189–3036 ng/mL) that were observed during the course of death investigations involving three children ranging in age from 1 week to 2 years, all of whom underwent withdrawal of life support. In all three cases, the presence of opiates in postmortem blood was indicated by immunoassay (ELISA) and quantitative confirmatory analysis of free morphine concentrations in postmortem blood was performed by solid-phase extraction followed by gas chromatography/mass spectrometry (GC/MS) in the selected ion monitoring mode. While the practice of withdrawing life support from terminally ill patients, with the accompanying administration of narcotics/analgesics has been reported in the medical literature, it has not been adequately described in the forensic literature. The implications of this practice on the forensic toxicological interpretation of morphine findings are discussed. To our knowledge, this is the first report of postmortem morphine concentrations arising directly from administration in conjunction with withdrawal of care in pediatric patients.     

Dominance of pre-analytical over analytical variation for measurement of methadone and its main metabolite in postmortem femoral blood

On the basis of simultaneously sampled postmortem blood specimens from the left and right femoral veins the pre-analytical variation of methadone measurements was evaluated and compared to the analytical variation. The material consisted of a series of 27 duplicate samples from routine autopsy cases comprising mainly drug addicts. A chiral LC-MS/MS method was used for measurement of the R- and S-enantiomers of methadone and its main metabolite 2-ethyl-1,5-dimethyl-3,3-diphenylpyrrolinium (EDDP). The analytical CV% was determined to be in the range 3-4% for methadone enantiomers and 4-6% for EDDP enantiomers. The total measurement uncertainty (CV(T)) was estimated from the pre-analytical variation (CV(PA)), analytical variation proper (CV(A)), and variation related to calibration (traceability) (CV(Cal)) according to the relationship CV(T) = [CV(2)(PA) + CV(2)(A) + CV(2)(cal)](0.5). Uncertainty related to calibration concerned a component related to the purity of drug reference compound and a contribution from the production of calibrator solutions (CV(Cal)<1%). Pre-analytical sampling variation was estimated from the duplicate measurements of blood samples after subtraction of the analytical component. The pre-analytical variation amounted to a CV% of 19-21% for R- and S-methadone and 30-38% for R- and S-EDDP, i.e. considerably larger than the other components. Due to the squared addition principle, the resulting total uncertainty (CV(T)) became largely identical to the CV(PA), i.e. 19-21% for R- and S-methadone and 31-38% for R- and S-EDDP enantiomers. Accordingly, CV(T) exceeded CV(A) by a factor 5 or more. Dominance of the pre-analytical component of variation may also be likely for other compounds measured in postmortem blood samples. Thus, the width of the 95%-uncertainty interval (+/-2CV(T)) for a postmortem measurement is largely determined by the pre-analytical component of variation. This should be kept in mind when judging on the uncertainty of postmortem measurement results.     

Hair analysis for cocaine: factors in laboratory contamination studies and their relevance to proficiency sample preparation and hair testing practices

Since the introduction in 2001 of a urine-based detection method for recombinant erythropoietin (rHuEPO), transfusion-doping practices have regained interest. To address this problem, an efficient antidoping test designed to obtain direct proof of allogeneic blood transfusion was developed and validated. This test, based on flow cytometry analysis of red blood cell (RBCs) phenotypes, was used to determine the absence or the presence of numerous RBCs populations in a blood sample. A such, it may constitute a direct proof of an abnormal blood population resulting from homologous transfusion. Single-blind and single-site studies were carried out to validate this method as a forensic quality standard analysis and to allow objective interpretation of real cases. The analysis of 140 blood samples containing different percentages (0-5%) of a minor RBCs population were carried on by four independent analysts. Robustness, sensitivity, specificity, precision and stability were assessed. ISO-accredited controls samples were used to demonstrate that the method was robust, stable and precise. No false positive results were observed, resulting in a 100% specificity of the method. Most samples containing a 1.5% minor RBCs population were unambiguously detected, yielding a 78.1% sensitivity. These samples mimicked blood collected from an athlete 3 months after a homologous blood transfusion event where 10% of the total RBCs present in the recipient originated in the donor. The observed false negative results could be explained by differences in antigen expression between the donor and the recipient. False negatives were more numerous with smaller minor RBCs populations. The method described here fulfils the ISO-17025 accreditation and validation requirements. The controls and the methodology are solid enough to determine with certainty whether a sample contains one or more RBCs populations. This variable is currently the best indicator for homologous blood transfusion doping.     

金龙蛤蚧平喘胶囊治疗稳定期慢性阻塞性肺疾病临床观察

目的 观察金龙蛤蚧平喘胶囊治疗稳定期慢性阻塞性肺疾病（chronic obstructive pulmonary disease,COPD）的疗效。方法 将58例COPD患者随机分为治疗组和对照组,每组28例。在常规治疗基础上,分别给予金龙蛤蚧平喘胶囊与安慰剂。治疗前、治疗6个月后和治疗12个月后,分别观察两组患者的肺功能、骨密度（bone mineral density,BMD）、BODE指数、COPD评估测试（COPD assessment test,CAT）问卷评分及1年内急性加重次数。结果 治疗6个月后及治疗12个月后,两组肺功能各项参数比较,差异均无统计学意义（P＞0.05）。 治疗12个月后,治疗组股骨颈BMD较治疗前显著升高（P＜0.05）,而对照组股骨颈BMD较治疗前显著下降（P＜0.05）。治疗6个月后和治疗12个月后,两组BODE指数及其因子6 min步行距离积分比较,差异均有统计学意义（P＜0.05）。两组1年内急性加重次数相比,差异具有统计学意义（P＜0.05）。结论 金龙蛤蚧平喘胶囊可有效改善稳定期COPD患者的肺功能、BODE指数及生活质量,减少患者1年内急性加重次数。