Characterization and Differentiation of Geometric Isomers of 3‐methylfentanyl Analogs by Gas Chromatography/Mass Spectrometry,Liquid Chromatography/Mass Spectrometry,and Nuclear Magnetic Resonance Spectroscopy

The cis and trans isomers of 3‐methylfentanyl and its three analogs were chemically synthesized, and these compounds were characterized and differentiated by gas chromatography/mass spectrometry (GC/MS), liquid chromatography/mass spectrometry (LC/MS), and nuclear magnetic resonance (NMR) spectroscopy. The cis and trans isomers of the 3‐methylfentanyl analogs were completely separated by GC/MS. Although the high temperature of the GC injection port caused thermal degradation of β‐hydroxy‐3‐methylfentanyl, the degradation was completely suppressed by trimethylsilyl derivatization. The isomers were also well separated by LC/MS on an octadecylsilyl column with 10 mM ammonium acetate and methanol as the mobile phase. The proton NMR signals were split when the hydrochloride salts of the 3‐methylfentanyl analogs were dissolved in deuterated chloroform because stereoisomers were formed by the coordination of the hydrochloride proton to the nitrogen of the piperidine ring of the 3‐methylfentanyl analogs.     

柱前衍生化反相高效液相色谱法测定蝉蜕中3种氨基酸含量

目的 建立柱前衍生化反相高效液相色谱法测定蝉蜕中天冬氨酸、酪氨酸和缬氨酸3种氨基酸含量的方法。方法 采用酸水解法制备氨基酸样品溶液,以异硫氰酸苯酯柱前衍生化后进行高效液相色谱分析。采用Kromasil C18色谱柱(250 mm×4.6 mm),梯度洗脱,流动相A为0.1 mol/L醋酸钠缓冲液- 乙腈(93∶7),流动相B为乙腈- 水(4∶1),流速1.0 mL/min,柱温为43 ℃,检测波长254 nm,进样量20 μL。结果 氨基酸衍生溶液在36 h内保持稳定,3种氨基酸在线性范围内峰面积与浓度的相关系数均大于0.999 0,加样回收率(n＝6)分别为95.62%、101.26%和100.00%。结论 所建立的检测方法稳定可靠,精密度和重复性良好,可用于蝉蜕中天冬氨酸、酪氨酸、缬氨酸含量测定。     

Chlorpyrifos Determined in Human Blood by UPLC-MS/MS and Its Application in Poisoning Cases

Objective To determine the chlorpyrifos in human blood by liquid chromatography-tandemmass spectrometry and to validate its application in poisoning cases. Methods The samples were extracted by a simpl...     

Quantitation of Synthetic Cannabinoids in Plant Materials Using High Performance Liquid Chromatography with UV Detection (Validated Method)

Plant based products laced with synthetic cannabinoids have become popular substances of abuse over the last decade. Quantitative analysis for synthetic cannabinoid content in the laced materials is necessary for health hazard assessments addressing overall exposure and toxicity when the products are smoked. A validated, broadly applicable HPLC‐UV method for the determination of synthetic cannabinoids in plant materials is presented, using acetonitrile extraction and separation on a commercial phenylhexyl stationary phase. UV detection provides excellent sensitivity with limits of quantitation (LOQs) less than 10 μg/g for many cannabinoids. The method was validated for several structural classes (dibenzopyrans, cyclohexylphenols, naphthoylindoles, benzoylindoles, phenylacetylindoles, tetramethylcyclopropylindoles) based on spike recovery experiments in multiple plant materials over a wide cannabinoid contents range (0.1–81 mg/g). Average recovery across 32 cannabinoids was 94% for marshmallow leaf, 95% for damiana leaf, and 92% for mullein leaf. The method was applied to a series of case‐related products with determined amounts ranging from 0.2 to >100 mg/g.     

HPLC测定爽咽茶中绿原酸的含量

目的：建立爽咽茶中绿原酸含量的测定方法。方法：采用HPLC测定炎咽茶中绿原酸的含量，采用C18柱，乙腈-4．0g／L磷酸(10：90)为流动相，检测波长为327nm。结果：平均加样回收率为97．75％，RSD为1．40％。结论：本法操作简便、易行，具有实用性。     

短柄乌头急性中毒——乌头碱在大鼠体内分布的研究

本文用高效液相色谱法检测了大白鼠短柄乌头急性中毒后(LD_(50)剂量灌胃),乌头碱在心、肝、肾、血、脑内的含量分布。结果表明;体内乌头碱含量甚微或检不出。30例大鼠LD_(50)剂量灌胃后,16例2h内中毒死亡。其肝、肾内的乌头碱检出率明显高于心、血、脑,且中毒表现明显。另14例于2h整处死,其肝、肾、血中检出较高。16例2h内死亡组肝中乌头碱含量分析提示乌头碱在体内代谢很快。此结果为法医工作中乌头碱中毒案件调查、检材提取、毒物分析结果的评价提供了一定的依据。     

论尿液中麦角酰二乙胺及其代谢物的分析研究

本文介绍了一种简便而快速的液质联用方法用于尿液中的麦角酰二乙胺和2-氧基-3-羟基-麦角酰二乙胺的定性定量分析。所有的分析都是在Agilent1100液质联用系统上进行的。在25-500pg/ml的浓度范围内,其校正曲线的相关因子是大于0.99。利用液/质方法得到的结果,其准确度和精密度都非常高,而且与GC/MS/MS的结果一致。因此液/质方法可以用于尿样中麦角酰二乙胺和2-氧基-3-3羟基-麦角酰二乙胺的定量分析。     

Citrate Content of Bone as a Measure of Postmortem Interval: An External Validation Study

The postmortem interval (PMI) of skeletal remains is a crucial piece of information that can help establish the time dimension in criminal cases. Unfortunately, the accurate and reliable determination of PMI from bone continues to evade forensic investigators despite concerted efforts over the past decades to develop suitable qualitative and quantitative methods. A relatively new PMI method based on the analysis of citrate content of bone was developed by Schwarcz et al. The main objective of our research was to determine whether this work could be externally validated. Thirty‐one bone samples were obtained from the Forensic Anthropology Center, University of Tennessee, Knoxville, and the Onondaga County Medical Examiner's Office. Results from analyzing samples with PMI greater than 2 years suggest that the hypothetical relationship between the citrate content of bone and PMI is much weaker than reported. It was also observed that the average absolute error between the PMI value estimated using the equation proposed by Schwarcz et al. and the actual (“true”) PMI of the sample was negative indicating an underestimation in PMI. These findings are identical to those reported by Kanz et al. Despite these results this method may still serve as a technique to sort ancient from more recent skeletal cases, after further, similar validation studies have been conducted.     

室外温度与室内恒温下EC随死后经历时间的变化

目的在室外环境和室内恒温条件下测定昼夜不同时间猪后腿肌肉电导率(electrical conductivity,EC)值,分析并比较两种环境条件下,EC值随死后经历时间(time since death, TSD)变化的规律。方法取5块即刻屠宰的猪后腿肌肉,均分为两份,随机分成两组,分别置于秋季室外环境和室内18℃恒温环境中。在死后10d内分别于早晚8时(每隔12h)取样,测定其浸渍液EC值。结果两种环境条件下,EC随TSD变化的趋势在整体上是一致的,二者相关性均较好(R2室外=0.971,P室外=0.004,R2室内=0.98,P室内=0.002)。室外环境温度下,肌肉的EC值在白天增长明显,夜间增长不明显,尤其环境温度低于13℃时,出现明显的平台现象,与室内恒温条件下肌肉EC值持续上升的变化趋势有显著的差异。结论无论室外环境温度还是室内恒温下,肌肉EC与TSD的相关性均较好,但在具体分析时,应考虑到夜间低温平台期造成的时间延搁。     

Determination of triptolide and wilforlide A in biological samples by LC-MS/MSCSCD

Objective: To determinate triptolide and wilforlide A in biological samples by liquid chromatography-tandem mass spectrometry (LC-MS/MS) method and to verify the method. Methods: After 0.4 mL blood, urine or 0.4 g hepatic tissues with internal standard were extracted by ethyl acetate, they were separated on a Allure PFP Propyl (100 mm × 2.1 mm, 5 μm) with a mobile phase of methanol-20 mmol/L ammonium acetate using gradient elution. For mass spectrometric detection, electrospray ionization (ESP) in positive mode was elected and the data was collected using multiple-reaction monitoring (MRM). Results: The linearity was good (r>0.9950) and the limit of detection was 2 ng/mL or 2 ng/g for triptolide and wilforlide A. The recovery was 61.08%-102.98%. The intra-day and inter-day precision was less than 12.58% for each biological sample, and the accuracy was 90.61%-105.80%. Conclusion: This method is simple, convenient and good selective, and could be applied to analysis of triptolide and wilforlide A in different biological samples. And the method may provide technical support for forensic medicine identification, clinical diagnosis and treatment of tripterygium wilfordii Hook. f. poisoning. © 2015 by the Editorial Department of Journal of Forensic Medicine.