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41.
Drug-facilitated sexual assault (DFSA) has been defined as the use of a chemical agent to facilitate a sexual assault. We report two cases of the use of tetrahydrozoline for DFSA. We believe this is the first report with urinary quantification of tetrahydrozoline levels postassault. Blood and urine were obtained c. 20 h postexposure in two cases of reported DFSA. Tetrahydrozoline was not detected in blood but was identified in urine in both victims. After initial identification in the urine using the 2010 update to the AAFS mass spectrometry database library, tetrahydrozoline was quantified at 114 and 150 ng/mL, respectively, using GC/MS. Two unique clinical features reported in these cases were intermittent periods of consciousness and postexposure vomiting. Use of GC/MS was successful in identifying tetrahydrozoline in the 100 ng/mL range up to 20 h postexposure. For victims with late presentation, urine may be a better sample for evaluation for tetrahydrozoline. 相似文献
42.
Abstract: Consumer complaints received by the U.S. Food and Drug Administration in August 2010 about raw organic almonds tasting “bitter” opened an investigation into the presence of bitter almonds in the imported product. Bitter almonds (Prunus amygdalus) contain the cyanogenic glucoside amygdalin, which hydrolyzes to produce cyanide. Ultraviolet–visible spectrophotometry was used to detect and quantitate cyanide, and liquid chromatography‐mass spectrometry was utilized to detect amygdalin in the submitted samples. Control bitter almonds were found to contain 1.4 mg cyanide/g and an estimated level of 20–25 mg amygdalin/g. The questioned samples contained between 14 and 42 μg cyanide/g and were positive for the presence of amygdalin. Sweet almonds were found to be negative for both compounds, at levels of detection of 4 μg cyanide/g and 200 μg amygdalin/g. 相似文献
43.
Biao Li M.Sc. Peng Xie Ph.D. Ying‐min Guo B.Sc. Qing Fei B.Sc. 《Journal of forensic sciences》2014,59(2):543-549
In many criminal and civil cases in China, the most commonly questioned documents are those written with gel pen ink. An important task for forensic document examiners is to identify whether two or more ink entries in one or more documents were written with the same ink type. The identification of the age of gel ink entries made poses an important and difficult problem for forensic document examiners. In this paper, the volatile components of gel ink were determined and the gel ink was classified by gas chromatography with a flame ionization detector. Calibration curves were created to express the relationship between the content of volatile gel ink components and the age of gel ink entries stored under natural and UV‐induced aging conditions. The correspondence between the natural and UV‐induced aging conditions was also established. The experimental results showed that GC was useful in the analysis of black gel ink and applicable for determining the relative age of gel ink entries under certain conditions. 相似文献
44.
45.
Organic impurity profiling of fentanyl samples associated with recent clandestine laboratory methods
Steven G. Toske PhD Jennifer R. Mitchell MS James M. Myslinski PhD Andrew J. Walz PhD David B. Guthrie PhD Elizabeth M. Guest PhD Charlotte A. Corbett PhD Emily D. Lockhart MS 《Journal of forensic sciences》2023,68(5):1470-1483
Nearly a decade ago, fentanyl reappeared in the United States illicit drug market. In the years since, overdose deaths have continued to rise as well as the amount of fentanyl seized by law enforcement agencies. Research surrounding fentanyl production has been beneficial to regulatory actions and understanding illicit fentanyl production. In 2017, the Drug Enforcement Administration (DEA) began collecting seized fentanyl samples from throughout the United States to track purity, adulteration trends, and synthetic impurity profiles for intelligence purposes. The appearance of a specific organic impurity, phenethyl-4-anilino-N-phenethylpiperidine (phenethyl-4-ANPP) indicates a shift in fentanyl production from the traditional Siegfried and Janssen routes to the Gupta-patent route. Through a collaboration between the DEA and the US Army's Combat Capabilities Development Command Chemical Biological Center (DEVCOM CBC), the synthesis of fentanyl was investigated via six synthetic routes, and the impurity profiles were compared to those of seized samples. The synthetic impurity phenethyl-4-ANPP was reliably observed in the Gupta-patent route published in 2013, and its structure was confirmed through isolation and structure elucidation. Organic impurity profiling results for illicit fentanyl samples seized in late 2021 have indicated yet another change in processing with the appearance of the impurity ethyl-4-anilino-N-phenethylpiperidine (ethyl-4-ANPP). Through altering reagents traditionally used in the Gupta-patent route, the formation of this impurity was determined to occur through a modification of the route as originally described in the Gupta patent. 相似文献
46.
Kymeri Davis MS Madison Reavis MS John V. Goodpaster PhD 《Journal of forensic sciences》2023,68(3):815-827
The storage and use of explosives is regulated at the state and federal level, with a particular focus on physical security and rigorous accounting of the explosive inventory. For those working with explosives for the training and testing of explosive-detecting canines, cross-contamination is an important concern. Hence, explosives intended for use with canine teams must be placed into secondary storage containers that are new, clean, and airtight. A variety of containers meet these requirements and include screw-top glass jars (e.g., mason jars). However, an additional need from the explosive-detecting canine community is secondary containers that can also be used as training aids whereby the volatiles emitted by explosives are emitted in a predictable and stable manner. Currently, a generally accepted method for the storage of explosives and controlled emission of explosive vapor for canine detection does not exist. Ideally, such containers should allow odor to escape from the training aid but block external contaminates such as particulates or other volatiles. One method in use places the explosive inside a permeable cotton bag when in use for training and then stores the cotton bag inside an impermeable nylon bag for long-term storage. This paper describes the testing of an odor permeable membrane device (OPMD) as a new way to store and deploy training aids. We measured the evaporation rate and flux of various liquid explosives and volatile compounds that have been identified in the headspace of actual explosives. OPMDs were used in addition to traditional storage containers to monitor the contamination and degradation of 14 explosives used as canine training aids. Explosives were stored individually using traditional storage bags or inside an OPMD at two locations, one of which actively used the training aids. Samples from each storage type at both locations were collected at 0, 3, 6, and 9 months and analyzed using Fourier Transform Infrared (FTIR) Spectroscopy and Gas Chromatography–Mass Spectrometry (GC–MS) with Solid-Phase Microextraction (SPME). FTIR analyses showed no signs of degradation. GC–MS identified cross-contamination from ethylene glycol dinitrate (EGDN) and/or 2,3-dimethyl-2,3-dinitrobutane (DMNB) across almost all samples regardless of storage condition. The contamination was found to be higher among training aids that were stored in traditional ways and that were in active use by canine teams. 相似文献
47.
Evaluating the discriminating power of amino acid ratios on distinguishing dark colored hair samples
Timothy Yaroshuk MS Robert H. Powers PhD Alyssa L. M. Marsico PhD 《Journal of forensic sciences》2023,68(2):416-424
Human hairs are one of the most commonly encountered items of trace evidence. Currently, conventional methods for hair analysis include microscopic comparison and DNA analysis (nuclear and mitochondrial). Each approach has its own drawbacks. Hair proteins are stable and offer an alternative to DNA testing, as demonstrated with proteomics for distinguishing humans. However, proteomics is complicated and requires identifying peptides to remain intact following harsh sample preparation methods. Alternatively, the actual amino acid content of a hair sample may also offer important identifying information and actually requires proteins and peptides to be broken down completely rather than remaining intact. This study evaluated the discriminating power of using hair amino acid ratios to differentiate hair samples from 10 unrelated individuals with dark colored hair. Hair proteins were digested, derivatized, and analyzed using gas chromatography–mass spectrometry. Amino acid ratios were calculated for each individual and comparisons using ANOVA and post-hoc pairwise t-test with Bonferroni correction were made with amino acid ratios for individuals. Overall, out of the 45 possible pairwise comparisons between all hair samples, 38 (84%) were differentiable. Out of the 36 possible pairwise comparisons between brown haired individuals, 32 (89%) were considered differentiable using univariate statistics. Multivariate statistics were also attempted but, overall, univariate models were sufficient for exclusionary purposes. These results indicate that amino acid ratio analysis can potentially be used as an exclusionary method using hair if DNA analysis cannot be performed, or to corroborate conclusions made following microscopic analysis. 相似文献
48.
Monitoring of Levamisole Concentration in Serum of Traffic Participants after Cocaine Consumption 下载免费PDF全文
Marek Dziadosz Ph.D. Michael Klintschar Prof. M.D. Jörg Teske Ph.D. 《Journal of forensic sciences》2016,61(Z1):S250-S251
This study highlights the problem of levamisole‐adulterated cocaine in context of active traffic participation. For the purposes of levamisole concentration monitoring in human serum, an analytical method based on LC‐MS/MS and solid‐phase extraction was applied. A Luna 5 μm C18 (2) 100 A, 150 mm × 2 mm column and a mobile phase consisting of A (H2O/methanol = 95/5, v/v) and B (H2O/methanol = 3/97, v/v), both with 10 mM ammonium acetate and with 0.1% acetic acid (pH = 3.2), were used. The validation experiments demonstrated that the method applied was appropriate for levamisole quantification in human serum. For 23% of levamisole‐positive samples, the concentrations exceeded 20 ng/mL. Therefore, the interaction of this drug with cocaine has to be considered as important for active traffic participation. As a consequence, monitoring of levamisole concentration in human serum is recommended, as long as it is used as cocaine adulterant. 相似文献
49.
目的建立同时测定大麻植物中四氢大麻酚(tetrahydrocannabinol,THC)、大麻二酚(cannabidiol,CBD)和大麻酚(cannabinol,CBN)三种有效成分的高效液相色谱(HPLC)法。方法采用通用C_(18)色谱柱,以乙腈-磷酸盐缓冲液(0.015 mol/L KH_2PO_4)为流动相,流速为1.0 m L/min,检测波长为220 nm,同时收集波长190~400nm的紫外光谱图,并以此光谱图及保留时间作为定性依据。结果所建方法能良好地分离THC、CBD和CBN,三种成分在0.4~40μg/m L范围内线性关系良好(R~2≥0.999 3),回收率大于87%,最低检出限分别为1.8、2.0和1.3 ng,日内精密度与日间精密度均小于5%。结论反相HPLC法简便、快速、准确,适用于大麻植物中THC、CBD和CBN的定性定量检测。 相似文献
50.
Amvrosios Orfanidis M.Sc. Helen Gika Ph.D. Eleni Zaggelidou Ph.D. Orthodoxia Mastrogianni Ph.D. Nikolaos Raikos Ph.D. 《Journal of forensic sciences》2019,64(2):643-646
In several medico‐legal cases, bone samples analysis may provide the only source of toxicological information. This case study reports the analysis of a human bone specimen, belonging to a 46‐year‐old man, found 3 months after his death due to cervical–thoracic injuries in a motorcycle accident. Bone specimen was the only available material for toxicological analysis, among few skull hair and rotten skin. Analysis was performed by a newly developed and validated ultra‐high‐pressure liquid chromatography–mass spectrometry/mass spectrometry (UHPLC‐MS/MS) method, following simple and efficient sample pretreatment. The results were in accordance with the man's medical record: Alprazolam and zolpidem were found at 2.2 and 5.4 ng/g of bone, respectively. Both these drugs were prescribed to the deceased. 相似文献