固相萃取-气相色谱法提取全血中的外源性褪黑素

目的建立血样中褪黑素的固相萃取方法。方法采用OasisHLB固相萃取柱提取,GC/NPD定量检验,GC/MS定性检验。结果血样中褪黑素平均萃取回收率达80%以上,最低检出限0.02μg/mL,线性良好,相关系数R2=0.9978。结论该方法操作简便快速,提取回收率高,重现性好,提取物干净,可用于实际案件当中。     

全血中DNA6种提取方法的比较

目的 比较经典有机法、改良有机法、常规Chelex-100法、IQ法、Qiagen法及SP法6种方法在提取DNA纯度和得率上的差异.方法 收集10名健康志愿者的静脉全血各5mL,分别采用6种方法提取基因组DNA,通过紫外分光光度仪和荧光定量分析技术检测产物的纯度和浓度,计算得率,并使用统计软件对结果进行分析.结果 常规Chelex-100法所得DNA的纯度明显低于其他方法,而另外5种方法所得DNA纯度的差异不具有统计学意义.改良有机法得率最低,IQ法得率最高.统计结果表明试剂盒方法抽提全血DNA的得率明显高于经典有机法、常规Chelex-100法和改良有机法,其差异具有统计学意义.结论 与有机法和常规Chelex-100法相比,高质量试剂盒类方法更有利于法医学检材的DNA抽提.     

Automated DNA extraction using the QIAsymphony platform: Estimation of DNA recovery from simulated forensic stains

The aim of this study was to evaluate the forensic protocol recently developed by Qiagen for the QIAsymphony automated DNA extraction platform. Samples containing low amounts of DNA were specifically considered, since they represent the majority of samples processed in our laboratory. The analysis of simulated blood and saliva traces showed that the highest DNA yields were obtained with the maximal elution volume available for the forensic protocol, that is 200 μl. Resulting DNA extracts were too diluted for successful DNA profiling and required a concentration. This additional step is time consuming and potentially increases inversion and contamination risks. The 200 μl DNA extracts were concentrated to 25 μl, and the DNA recovery estimated with real-time PCR as well as with the percentage of SGM Plus alleles detected. Results using our manual protocol, based on the QIAamp DNA mini kit, and the automated protocol were comparable. Further tests will be conducted to determine more precisely DNA recovery, contamination risk and PCR inhibitors removal, once a definitive procedure, allowing the concentration of DNA extracts from low yield samples, will be available for the QIAsymphony.     

A dedicated automated system for extraction, quantification and STR amplification of forensic evidence samples

Forensic DNA analysis is a multi-step process involving extraction of DNA, quantification of human DNA in the extract, amplification using multiplex STR systems, separation of products, and data analysis. The backlog of forensic casework is increasing worldwide. Automation is one significant way to alleviate the bottleneck of sample processing in forensic labs. The HID EVOlution™ Combination System described here is a robust, reliable sample processing platform, easily adapted to forensic laboratory workflows. Using a variety of forensic sample types including: blood stained FTA paper, cotton fabric and denim, dried blood spiked with known PCR inhibitors, saliva on cotton swabs, and semen stains, we found that yields of human DNA and STR profiles obtained with AmpFlSTR^® Idenitfiler^® kits were complete, highly reproducible, and equivalent to results obtained using the manual PrepFiler™ reagent extraction method. Automated operation was clean, and no cross-contamination was detected between extraction blanks and interspersed high DNA content samples.     

Adaptation and evaluation of the PrepFiler™ DNA extraction technology in an automated forensic DNA analysis process with emphasis on DNA yield, inhibitor removal and contamination security

Within the initial step of the forensic DNA analysis process, the DNA extraction efficiency and especially the removal of potential PCR inhibitors is crucial for subsequent steps, e.g. quantification by real-time PCR and amplification of short tandem repeats (STRs). The protocol of the PrepFiler™ Forensic DNA Extraction Kit was optimized for the application on a Tecan liquid handling workstation Freedom EVO^® 150. This modified application of the PrepFiler™ technology was compared with respect to DNA yield, sensitivity and the ability to remove potential PCR inhibitors to an established routine method working on the same liquid handling workstation based on ChargeSwitch^® Technology (CST) from Invitrogen.     

死亡大鼠组织中总RNA提取的质量控制及方法评价

目的探讨不同商品化试剂盒在提取组织总RNA过程中的优劣与适用范围,为实验室的质量控制提供依据。方法采用以膜提取技术为基础（SV total RNA isolation system）和以异硫氰酸胍/苯酚法为原理（TRIzol总RNA提取试剂盒）的两种试剂盒对死亡大鼠心、肝、脾、肺、肾、脑组织进行总RNA的提取与评价鉴定,并使用琼脂糖变性凝胶电泳和2100芯片生物分析仪对提取的总RNA进行完整性鉴定和质量控制评价。结果两种商品化试剂盒提取的总RNA纯度与得率均可满足实验要求。各组织脏器中总RNA得率依次为脾脏＆gt;肝脏＆gt;肾脏＆gt;大脑＆gt;肺脏＆gt;心脏。结论与TRIzol总RNA提取试剂盒相比,SV Total RNA Isolation System提取时对操作人员熟练度要求较低,2100芯片生物分析仪有望替代凝胶电泳技术用于总RNA提取时的质量控制。     

固相萃取--紫外导数光谱法测定肝中心得安含量

文章给出了肝中心得安的固相萃取--紫外导数光谱法.肝中心得安用GDX403树脂吸附然后用甲醇洗脱,用二阶紫外导数光谱测定心得安的含量.该法简便快速,方法的回收率和检出限分别为80.6%±3.4%和1.8μg/g.     

分子印迹固相萃取技术-液相色谱法测定鱼塘水中2甲4氯苯氧乙酸

目的建立分子印迹固相萃取技术对鱼塘水中2甲4氯苯氧乙酸进行提取和分析的方法。方法以2甲4氯分子印迹聚合物为固相萃取材料,对鱼塘水中2甲4氯进行分离提取,洗脱液直接进行液相色谱分析。结果鱼塘水中MCPA的提取率在80%以上,检出限0.040μg/mL,在0.2μg/mL～2.0μg/mL范围内线性关系良好。结论该方法的准确度和精密度较好,适合实际发生案件的检测分析。     

固相萃取技术（SPE）在苯丙胺类毒品分析中的应用

固相萃取（SPE）技术是利用固体吸附剂将目标化合物吸附,使之与样品的基体及干扰化合物分离,从而达到分离和富集的目的。SPE是20世纪70年代后期发展起来的一种样品前处理技术,本文主要综述了近10年来SPE技术在苯丙胺类毒品分析中的应用现状及其趋势。     

快速溶剂萃取法及其在刑事技术中的应用

快速溶剂萃取技术是近几年出现的一种新的适用于复杂检材前处理的、高效、快速、简便、理想的萃取方法。快速溶剂萃取法的原理、特点、仪器装置与操作步骤、影响因素在刑事技术领域的应用。