分散固相萃取-GC/MS法测定人血中啶虫脒的含量

目的建立人血中新型农药啶虫脒的检验方法。方法用分散固相萃取法提取人血中啶虫脒,GC/MS/SIM法进行测定。结果在0.02μg/mL～2μg/mL添加水平范围内,线性关系良好,啶虫脒的平均添加回收率在76.4%～89.8%之间,相对标准偏差在1.3%～8.3%之间,啶虫脒的检出限为0.0075μg/mL。结论该方法操作简便,结果准确,适用于人血中啶虫脒的检验。     

ASE和GPC方法检验非苯二氮卓类催眠药

目的建立生物样品中4种非苯二氮卓类新型催眠药的快速溶剂萃取-凝胶色谱检验方法。方法生物样品采用快速溶剂萃取,凝胶色谱净化,GC／NPD检验。结果4种新型催眠药的平均回收率均在83％以上,检测限为0．05μg·mL-1～0．1μg·mL-1。结论该方法可满足实际检案的需求。     

Development of a rapid, 96-well alkaline based differential DNA extraction method for sexual assault evidence

We present a rapid alkaline lysis procedure for the extraction of DNA from sexual assault evidence that generates purified sperm fraction extracts that yield STR typing results similar to those obtained from the traditional organic/dithiothreitol differential extraction. Specifically, a sodium hydroxide based differential extraction method has been developed in a single-tube format and further optimized in a 96-well format. The method yields purified extracts from a small sample set (∼2-6 swabs) in approximately 2 h and from a larger sample set (up to 96 swabs) in approximately 4 h. While conventional differential extraction methods require vigorous sample manipulation to remove the spermatozoa from the substrate, the method described here exploits the propensity of sperm to adhere to a substrate and does not require any manipulation of the substrate after it is sampled. For swabs, sample handling is minimized by employing a process where the tip of the swab, including the shaft, is transferred to the appropriate vessel eliminating the need for potentially hazardous scalpels to separate the swab material from the shaft. The absence of multiple handling steps allows the process to be semi-automated, however the procedure as described here does not require use of a robotic system. This method may provide forensic laboratories a cost-effective tool for the eradication of backlogs of sexual assault evidence, and more timely service to their client agencies. In addition, we have demonstrated that a modification of the procedure can be used to retrieve residual sperm-cell DNA from previously extracted swabs.     

LC／MS／MS法测定生物组织中百草枯

目的建立LC／MS／MS检测生物体液中百草枯方法。方法弱阳离子交换固相萃取小柱提取剂，应用LC／MS／MS法对生物样品中百草枯进行定性定量分析。结果经该方法测得百草枯的最小检出限为10ng／ml血（S／N≥3），线性范围为0．02～20μg／ml。结论该方法快速、灵敏、准确，适用于生物检材中百草枯的分析。     

Single sperm cell isolation by micromanipulation for human identification in sexual assault

This study proposes a new alternative solution in preferential extraction methods or microdissection to isolate and analyse single sperm cells in case of sexual assault. After the transfer of swabs in liquid culture medium, perpetrator's spermatozoas can be physically separated from victim's epithelial cells by using classical techniques of micromanipulation as ICSI (IntraCytoplasmic Spermatozoa Injection), usually applied for IVF (In vitro Fertilization).     

The determination of psilocin and psilocybin in hallucinogenic mushrooms by HPLC utilizing a dual reagent acidic potassium permanganate and tris(2,2'-bipyridyl)ruthenium(II) chemiluminescence detection system

This paper describes a procedure for the determination of psilocin and psilocybin in mushroom extracts using high-performance liquid chromatography with postcolumn chemiluminescence detection. A number of extraction methods for psilocin and psilocybin in hallucinogenic mushrooms were investigated, with a simple methanolic extraction being found to be most effective. Psilocin and psilocybin were extracted from a variety of hallucinogenic mushrooms using methanol. The analytes were separated on a C12 column using a (95:5% v/v) methanol:10 mM ammonium formate, pH 3.5 mobile phase with a run time of 5 min. Detection was realized through a dual reagent chemiluminescence detection system of acidic potassium permanganate and tris(2,2'-bipyridyl)ruthenium(II). The chemiluminescence detection system gave improved detectability when compared with UV absorption at 269 nm, with detection limits of 1.2 x 10(-8) and 3.5 x 10(-9) mol/L being obtained for psilocin and psilocybin, respectively. The procedure was applied to the determination of psilocin and psilocybin in three Australian species of hallucinogenic mushroom.     

交通事故常见的微量物证及其提取方法

交通事故现场常见微量物证主要有油漆物证、塑料和树脂物证、纤维物证、橡胶和轮胎物证、汽车玻璃物证以及法医物证等。交通事故现场中的微量物证在确定事故责任和侦破交通肇事逃逸犯罪中起着至关重要的作用。因此 ,事故勘验人员应引起高度重视 ,注意掌握正确的提取方法。     

Pitfalls,challenges and caveats in whole mitochondrial genome sequencing from hair shafts by MPS: Where,when and how to address them

The growing use of massively parallel sequencing (MPS) for the whole mitochondrial genome analysis in forensic laboratories, requires the establishment of efficient workflows and interpretation procedures, to support the feasibility of the technology and the reliability of the data. In the case of reference samples, such as blood and buccal swabs, the generation of mtDNA profiles by using MPS is relatively simple. Conversely, many forensic casework samples still pose challenges for the MPS, data interpretation and reporting of mtDNA. This is especially true for the analysis of shed hairs, which are one of the most common evidence types and which are among the most limited in terms of DNA quantity and quality. Due to these limitations, every step involved in the analysis become essentials and should be performed in order to obtain the best performance, optimizing the outcomes and minimizing the errors.In light of this, we present a study focusing on the extraction, quantification and MPS of the whole mtDNA in hair shafts, with the aims of set-up and validate a methodological pipeline to obtain the best sequencing results. The overall performance of the MPS panel, mainly in terms of total coverage, amplicons coverage and different primer pools efficiency, was evaluated also in relation to the different hair fragments, the mtDNA copy number used for libraries preparation and its degradation state.     

河豚毒素的检验

通过对食用河豚鱼干致死案例的系统毒物分析,本文详细介绍了有关体内河豚毒素的固相萃取方法,利用本方法成功地解决了一起因河豚毒素中毒案件的检验,从死者胃内容、心血中均检出河豚毒素,从死者吃剩的干鱼片中检出1.4μg/g的河豚毒素.     

Sensitive Method for the Confident Identification of Genetically Variant Peptides in Human Hair Keratin

Recent reports have demonstrated that genetically variant peptides derived from human hair shaft proteins can be used to differentiate individuals of different biogeographic origins. We report a method involving direct extraction of hair shaft proteins more sensitive than previously published methods regarding GVP detection. It involves one step for protein extraction and was found to provide reproducible results. A detailed proteomic analysis of this data is presented that led to the following four results: (i) A peptide spectral library was created and made available for download. It contains all identified peptides from this work, including GVPs that, when appropriately expanded with diverse hair-derived peptides, can provide a routine, reliable, and sensitive means of analyzing hair digests; (ii) an analysis of artifact peptides arising from side reactions is also made using a new method for finding unexpected modifications; (iii) detailed analysis of the gel-based method employed clearly shows the high degree of cross-linking or protein association involved in hair digestion, with major GVPs eluting over a wide range of high molecular weights while others apparently arise from distinct non-cross-linked proteins; and (v) finally, we show that some of the specific GVP identifications depend on the sample preparation method.