Availability of target odor compounds from seized ecstasy tablets for canine detection

The aim of this study was to compare seized samples of 3,4-methylenedioxy-N-methylamphetamine (MDMA) pills, used to train law enforcement detection canine teams, to determine what differences exist in the chemical makeup and headspace odor and their effect on detectability. MDMA solutions were analyzed by liquid chromatography-mass spectrometry. Analysis of these samples showed a wide variance of MDMA (8-25%). Headspace SPME-GC/MS analysis showed that several compounds such as 3,4-methylenedioxyphenylacetone and 1-(3,4-methylenedioxyphenyl)-2-propanol are common among these MDMA samples regardless of starting compound and synthesis procedure. However, differences, such as the level of the various methylenedioxy starting compounds, were shown to affect the overall outcome of canine detection, indicating the need for more than one MDMA training aid. Combinations of compounds such as the primary odor piperonal in conjunction with a secondary compound such as MDP-2-OH or isosafrole are recommended to maximize detection of different illicit MDMA samples.     

Development and validation of a simple GC-MS method for the simultaneous determination of 11 anticholinesterase pesticides in blood--clinical and forensic toxicology applications

Anticholinesterase pesticides are widely used, and as a result they are involved in numerous acute and even fatal poisonings. The aim of this study was the development, optimization, and validation of a simple, rapid, specific, and sensitive gas chromatography-mass spectrometry method for the determination of 11 anticholinesterase pesticides (aldicarb, azinphos methyl, carbofuran, chlorpyrifos, dialifos, diazinon, malathion, methamidophos, methidathion, methomyl, and terbufos) in blood. Only 500 μL of blood was used, and the recoveries after liquid-liquid extraction (toluene/chloroform, 4:1, v/v) were more than 65.6%. The calibration curves were linear (R(2) ≥ 0.996). Limit of detections and limit of quantifications were found to be between 1.00-10.0 and 3.00-30.0 μg/L, respectively. Accuracy expressed as the %E(r) was found to be between -11.0 and 7.8%. Precision expressed as the percent relative standard deviation was found to be <9.4%. The developed method can be applied for the investigation of both forensic and clinical cases of accidental or suicidal poisoning with these pesticides.     

The Characterization of 3,4-Dimethylmethcathinone (3,4-DMMC)

Analogs and derivatives of traditional illicit drugs are ever increasing in variety and creativity. Staying abreast of the new developments is a constant challenge for every forensic laboratory. Recently, a seizure from Australian Customs Service presented our laboratory with the designer cathinone 3,4-dimethylmethcathinone (3,4-DMMC). Gas chromatography/mass spectrometry (GC/MS), liquid chromatography/mass spectrometry (LC/MS), nuclear magnetic resonance (NMR) spectroscopy, infrared (IR) spectroscopy, and ultraviolet (UV) spectrophotometry were employed to analyze the spectroscopic characteristics of this cathinone. As an analog, 3,4-DMMC exhibits similar if not identical IR and UV profiles to mephedrone (4-MMC) and methcathinone; however, the retention time from GC is unique as expected, and the electron impact fragmentation pattern is consistent with the fragmentation pattern of other cathinones. The chemical shifts of the carbons and hydrogens were assigned by both one- and two-dimensional NMR techniques, while the molecular weight was confirmed by LC/MS.     

高效液相色谱法鉴别染料型黑色喷墨打印字迹

目的建立液相色谱分析方法,对市售的30种不同厂家牌号（原装）染料型黑色喷墨打印字迹进行区分鉴别。方法通过选择最佳的提取条件、流动相,考察纸张、字迹形成方式等的影响,及样品及仪器的稳定性实验,确定实验条件。结果选择了最佳的反相高效液相色谱（RP-HPLC）分析方法：固定相为X-bridge Shield RP18（3.5μm,4.6×100mm）,流动相为乙腈-NH4HCO3溶液（10mmol/L）,梯度洗脱,检测波长为585nm、475nm;用该方法,根据字迹染料成分的差异将30种样品分为四大类17小类。结论该方法可以为鉴别区分不同厂家染料型黑色喷墨打印字迹提供依据。     

液相色谱-串联质谱法分析生物检材中的河豚毒素

目的建立血液、尿液以及肝中河豚毒素(tetrodotoxin,TTX)的液相色谱-串联质谱分析方法,并进行方法学验证。方法血液、尿液和肝用1%乙酸甲醇溶液去蛋白后,上清液用固相萃取法净化,LC-MS/MS检测。结果血液、尿液和肝中TTX检出限分别为2ng/mL、2ng/mL和4ng/g。血液和尿液在4～100ng/mL、肝在5～100ng/g的范围内线性关系良好,相关系数r≥0.9973;日内精密度和日间精密度均在12.80%以内;回收率大于47.2%。结论所建方法高效、灵敏、准确,可以为河豚毒素中毒的法医学鉴定、临床诊治以及食品安全的监控提供技术保障。     

Analysis of Gunshot Residue and Associated Materials—A Review

Abstract: A comprehensive review of the scientific literature on gunshot residue (GSR) is presented. Aspects of both inorganic and organic GSR are discussed, from formation and distribution, to sample collection, preparation, and analysis using a variety of techniques. The interpretation of GSR results is also considered including issues surrounding the contamination, distribution, and transfer of GSR. Potential problems with ulterior sources of GSR like particles have been reported in the literature. For example, particles from environmental and occupational sources have been highlighted as exhibiting similar chemical and morphological characteristics to GSR. These findings are put into context with regard to interpreting samples. A move toward a “case by case” approach is argued to be more preferable to a “formal” classification system where possible. The analysis of both inorganic and organic compositions of residue samples as well as morphological considerations is considered to be a more ideal approach to GSR analysis, whereever practicable.     

Determination of Adenosine Phosphates in Rat Gastrocnemius at Various Postmortem Intervals Using High Performance Liquid Chromatography

Abstract: Although the change in adenosine phosphate levels in muscles may contribute to the development of rigor mortis, the relationship between their levels and the onset and development of rigor mortis has not been well elucidated. In the current study, levels of the adenosine phosphates including adenosine triphosphate (ATP), adenosine diphosphate (ADP), and adenosine monophosphate (AMP) in gastrocnemius at various postmortem intervals of 180 rats from different death modes were detected by high performance liquid chromatography. The results showed that the levels of ATP and ADP significantly decreased along with the postmortem period of rats from different death mode whereas the AMP level remained the same. In addition, it was found that changes in the ATP levels in muscles after death correlated well with the development of rigor mortis. Therefore, the ATP level could serve as a reference parameter for the deduction of rigor mortis in forensic science.     

Determining the Toxicological Significance of Pregabalin in Fatalities

Pregabalin has become more widely prescribed and abused in recent years but is still not always included in laboratory analysis. An LC‐MS‐MS method has been developed and applied to measure pregabalin in 93 postmortem cases, including drug‐related deaths, alternative causes of death, and fatalities where pregabalin was likely to have contributed to death. Other drugs or alcohol was detected, and the most common drug types (in decreasing frequency) were antidepressants, opioids, benzodiazepines, opiates, alcohol, antipsychotics, cocaine, cardiac drugs, amphetamines, cannabis, anticonvulsants, and antihistamines. New psychoactive substances (methoxphenidine and synthetic cannabinoids) were only found in two cases. The results provide further data to assist in evaluating the significance of postmortem pregabalin concentrations and a toxicologically significant concentration of 25 mg/L is proposed. Pregabalin, especially with concomitant use of other CNS depressant drugs, presents a significant toxicological risk and existing laboratory protocols should be reviewed for their suitability to detect pregabalin.     

超高效液相色谱法测定四川松潘3种秦艽中马钱苷酸和龙胆苦苷的含量

目的 采用超高效液相色谱(ultra performance liquid chromatography,UPLC)法对四川省松潘地产3种秦艽中马钱苷酸和龙胆苦苷含量进行测定,并考察海拔高度对其含量的影响.方法 采用BEH C18 (2.1 mm×50 mm,1.7 μm)色谱柱,乙腈-0.1%醋酸溶液为流动相;流速...     

Quantification of Morphine,Codeine, and Thebaine in Home‐Brewed Poppy Seed Tea by LC‐MS/MS

Recently, medical examiners reported two cases of a 21‐year‐old male and 24‐year‐old male with high amounts of morphine in their blood at autopsy. It was suspected that the decedents ingested lethal amounts of morphine from home‐brewed poppy seed tea. No studies to date have investigated opium alkaloid content extracted from poppy seeds by home‐brewing methods. Various poppy seed products were purchased from online sources and extracted with four home‐brewing methods representative of recipes found on drug user forums. Morphine, codeine, and thebaine were quantified in the tea extracts by liquid chromatography‐tandem mass spectrometry using a validated analytical method. Morphine, codeine, and thebaine concentrations from seeds were <1–2788 mg/kg, <1–247.6 mg/kg, and <1–124 mg/kg, respectively. Alkaloid yield varied between extractions, but regardless of extraction conditions, lethal amounts of morphine can be rinsed from poppy seed coats by home‐brewing methods.