法医毒物检验中毒物的快速筛查与检测研究进展

法医毒物学检验工作的需求,已从单一种类毒物检验逐渐转向多目标毒物筛查和常见未知毒物筛查。免疫法、液相色谱质谱联用法、气相色谱质谱法及未知物筛查技术是目前常用的毒物筛查技术和方法,这些方法和技术都有其特点。本文综述了目前已开发的毒物快速筛查技术和方法,并对各种方法的优缺点和应用价值进行了评价,希望能为法医毒物学检验工作中毒物的快速筛查提供参考和借鉴。     

气质联用SIM技术在毒物检测中的应用

目的　介绍气质联用SIM技术在毒物检测中的应用方法。方法　通过两个案例对质谱的两种扫描方法fullscan(全扫描 )和SIM (选择离子检验 )进行了比较。结果　SIM技术检验灵敏度远远高于Full Scan技术。结论　SIM技术是最理想的微量毒物检测技术之一。     

气相色谱仪双毛细管柱双检测器技术在毒物检测中的应用

目的利用双毛细管柱双检测器技术建立常见毒物的检验方法,并对其进行定性分析。方法样品进样后通过VSOS装置进入两根不同极性的毛细管柱,经分离后到达两个不同选择性的检测器。结果利用VSOS装置可对毒物进行较好的分离、定性。结论该方法可对常见毒物进行准确定性。     

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。     

国外毒物分析进展概况

<正> 随着大量新药物和毒物的不断出现,以及犯罪分子利用药物、毒物进行犯罪的手段变得更加狡猾,因而对法庭毒物分析的要求也越来越高。例如微量毒物、复合毒物、毒物代谢产物的检验,骨髓、骨髂、毛发等检材中微量或痕量毒物的检验,目前常规的分析方法和分析仪器已经难以满足其分析要求。近年来,随着科学技术的发展,先进的分析仪器和分析方法在毒物分析领域中的应用,完全满足了现代毒物分析的要求,解决了许多毒物分析中的难题,使毒物分析的水平产生了新的飞跃。本文对近年来有机毒物分析的发展概况作简要介绍。     

法医毒物检验技术方法的评价方式

评价方式是评价技术中的重要组成部分。根据法庭科学领域毒物检验方法的技术特性与质量要求,在明确评价目标与原则的基础上,以评价指标为核心提出合理化的、可操作的评价方式。建立有效的评价方式,旨在通过科学的评价活动获得客观的评价结果。     

法医毒物鉴定的发展及其问题分析

文章阐述了法医毒物鉴定在对象种类、适用检材、技术方法、应用领域和结果运用方面的发展趋势,分析了现阶段我国毒物鉴定实验室在规范建设、鉴定能力、技术系统和质量控制中存在的问题和缺陷,提出要通过加强鉴定机构及鉴定人的准入控制,建设一支高资质、高水平的队伍;通过执业监管、认证认可、水平测试和质量评估,保障毒物鉴定结果的可靠、准确.     

UPLC-Q-TOF/MS法在毒物检测领域应用研究进展

超高效液相色谱-串联四极杆飞行时间质谱技术作为一种新的检验、筛查技术,具有检测范围宽、分析速度快、灵敏度高、数据库共享程度高等优点,其在毒物检测领域的应用有必要进行总结概括,拓宽思路。结合近年来UPLC-Q-TOF/MS技术和该技术在毒物检验领域内应用方面的文章,概述了该技术的基本原理,分析了UPLCQ-TOF/MS技术在农药、违禁药物、植物源性毒素等常见毒物检测领域的研究进展和优劣势。对其未来在法庭科学检验鉴定方面的工作进行了总结和展望。该技术自出现以来不断进步,为研究者提供了更好的研究手段,已经越来越多应用于各类型检测领域,同时在法庭科学毒物检验鉴定领域的应用也越来越广泛。     

法庭科学痕迹检验实验室质量控制的现状及进展

痕迹检验实验室作为法庭科学实验室的重要组成部分,其质量控制活动在遵循普遍原则的基础上,根据自身专业特性,在质量控制方法选择及活动实施上有所侧重.本文在调研国内外关于痕迹检验实验室质量控制研究与实践的基础上,从结果质量控制、人员资格和培训、方法确认、记录、结果报告、出庭等方面对痕迹检验实验室质量控制要求及现状进行综述,旨在探索痕迹检验实验室的质量控制关键技术,尽快建立国内痕迹检验实验室质量控制规范.     

常见毒物的X射线衍射法检验

目的建立X射线衍射的检验方法为其在毒物分析领域的应用提供参考。方法使用X射线衍射仪对常见毒物进行定性分析。结果X射线衍射检验常见毒物快速而且准确。结论该方法具有很强的实用性。     

Comparison of two methods for isolating DNA from human skeletal remains for STR analysis

Abstract: The quality and efficiency of a standard organic DNA isolation method and a silica‐based method using the QIAGEN Blood Maxi Kit were compared to obtain human DNA and short tandem repeats (STRs) profiles from 39 exhumed bone samples for paternity testing. DNA samples were quantified by real‐time PCR, and STR profiles were obtained using the AmpFlSTR^® Identifiler^® PCR amplification kit. Overall, the silica‐based method recovered less DNA ranging from 0 to 147.7 ng/g (average 7.57 ng/g, median = 1.3 ng/g) than did the organic method ranging from 0 to 605 ng/g (average 44.27 ng/g, median = 5.8 ng/g). Complete profiles (16/16 loci tested) were obtained from 37/39 samples (95%) using the organic method and from 9/39 samples (23%) with the silica‐based method. Compared with a standard organic DNA isolation method, our results indicate that the published silica‐based method does not improve neither the quality nor the quantity of DNA for STR profiling.     

法医学鉴定质量评价与控制研究

目的探讨法医学鉴定质量评价与控制的有效途径。方法根据法医学鉴定的要求,选择评价指标、评价等级以及确定权重指数,应用模糊数学综合评判的方法,对法医学鉴定质量进行评价与控制,并结合实例分析如何应用模糊数学综合评判的方法对法医学鉴定质量进行评价与控制。结果该方法对法医学鉴定质量具有有效的评价与控制。结论模糊数学综合评判可作为法医学鉴定质量评价与控制的有效手段。     

差异提取试剂盒在混合斑DNA提取中的应用

目的评估差异提取试剂盒对混合斑样本中的精子和上皮细胞DNA分离提取的有效性。方法采用差异提取试剂盒,选择性裂解精细胞和上皮细胞,结合磁珠法分别对人为控制条件下制备的模拟混合样本和案件中的混合斑检材进行精细胞DNA和上皮细胞DNA的分离提取。对所提取的DNA进行定量分析和STR分型。结果该试剂盒能从精子和上皮细胞不同比例的混合斑中提取出高纯度的精细胞和上皮细胞DNA。结论该差异提取试剂盒适用于性侵害案件中混合斑检材的DNA提取。     

Quantifying and Ranking Quality for Acquired Recordings on Digital Video Recorders

As the closed-circuit television (CCTV) security industry transitioned from analog media to digital video recorders (DVRs) with digital storage, the law enforcement community struggled with the means with which to collect the recordings. New guidelines needed to be established to determine the collection method which would be efficient as well as provide the best quality evidence from live DVRs. A test design was developed to measure, quantify, and rank the quality of acquisition methods used on live systems from DVRs typically used in digital CCTV systems. The purpose was to determine guidelines for acquiring the best quality video for investigative purposes. A test pattern which provided multiple quantifiable metrics for comparison between the methods of acquisition was used. The methods of acquisition included direct data download of the proprietary file and open file format as well as recording the video playback from the DVR via the available display monitor connections including the composite video, Video Graphics Array (VGA), and high-definition multimedia interface (HDMI). While some acquisition methods may provide the best quality evidence, other methods of acquisition are not to be discounted depending on the situation and need for efficiency. As an investigator that needs to retrieve video evidence from live digital CCTV systems, the proprietary file format, overall, provides the best quality evidence. However, depending on the circumstance and as recording technology continues to evolve, options other than the proprietary file format may provide quality that is equal to or greater than the proprietary file format.     

DNA profiles from biological trace material contained in underwear and toothbrushes

There are special cases where it is extremely difficult to find a close relative for obtaining reference samples, such as in adoption cases or foreigners without relatives in the country. In these cases, it is possible to use personal objects from the missing person. We developed a protocol for obtaining DNA profiles from toothbrushes and underwear and evaluated two DNA extraction methods (Silica and magnetic particles), comparing the DNA quantity and the quality of the obtained profiles. Results showed that for underwear, silica in suspension recovered higher DNA quantity but magnetic particles (PrepFiler®) generated more complete profiles. For toothbrushes PrepFiler® recovered a higher DNA quantity and generated more complete DNA profiles. Statistical analyses showed there were no significant differences between both methods. Higher DNA quantities were recovered from underwear samples, however toothbrushes generated higher quality in DNA profiles, without obtaining mixed profiles, concluding that toothbrushes are a better item than underwear. Considering that silica in suspension method is three-times cheaper than PrepFiler®, we propose it is possible to successfully obtain DNA profiles from personal objects using a low-cost DNA extract method.     

Development of Latent Fingermarks on Surfaces of Food‐A More Realistic Approach

Latent fingermark developing methods from food (mandarin, egg, banana, apple, potato, carrot, eggplant, onion, bell pepper, and tomato) surface has been studied by 10 methods, including powdering method, small particle reagent method, and cyanoacrylate fuming method. The foods were stored under two conditions (room temperature and refrigerator) before fingermark deposition and aged for 2, 24, 48, and 72 h before fingermark development. In most of the food surfaces used in this study, cyanoacrylate fuming with 80% relative humidity was superior to the powder or small particle reagent methods. The quality of the fingermarks varied depending on the storage conditions before the fingermark deposition (in the refrigerator or at ambient temperature) and the time elapsed since the fingermark deposition. However, the storage conditions before the fingermark deposition and the time elapsed since the fingermark deposition did not show any correlation with the quality of the fingermark.     

Rapid genomic DNA extraction (RGDE)

Hyperpolymorphic short tandem repetitive DNA sequences, STRs or microsatellites, have become widely used in human identification, particularly in criminal cases and in mass disasters. In such cases the substrates for the analyses may be decomposed as a biological material, a fact that has to be taken into account when choosing the appropriate casework methods. Nowadays expanded windows have been opened to the world especially in the area of genetic and biology science by performance of big projects such as human genome project. In this regard, one of the primary and important steps for all is DNA extraction with high quality and quantity in minimum time from biological material. By using RGDE method, genomic DNA with high quality and quantity can be acquired in the shortest time which has been presented in the world up to now. In this paper we report the evaluation of DNA extraction in this method.     

Liquid/solid extraction on diatomaceous earth for drug analysis in postmortem blood

Absorption extraction on diatomaceous earth was examined and found to be compatible with typical postmortem blood specimens encountered in forensic toxicology. The effects of solvent, solvent volume, eluate flow rate, and pH on drug recovery and extract quality were investigated. It was concluded that the best method was not necessarily that with the highest recoveries, but that considerations of extract quality were also required. The optimized method was compared with a single-step liquid/liquid extraction method and found to be superior in terms of ease of operation, extract quality, and absolute recovery. The results indicated also that although useful for screening, quantitative methods using liquid/solid extraction may be prone to error.     

英国律师按条件收费对我国律师风险代理制度的启示

按条件收费是英国借鉴美国律师采用的按判决金额收费方式而实施的一种将律师收费与其所代理案件结果相联系的收费方式.这样的收费方式,增大了普通民众接近司法的机会,提高了其接受高质量法律服务的可能性,对促进社会弱势群体的利益保护有着积极的意义.借鉴其成功的经验,将有助于推动我国律师风险代理制度的完善.