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1.
4-Methylmethamphetamine has been detected in samples submitted for analysis in several states throughout Australia. Six ring substituted methyl isomers of methamphetamine and amphetamine were synthesised and analysed. As the regioisomeric 2-, 3- and 4-methylmethamphetamine and 2-, 3- and 4-methylamphetamine have virtually identical mass spectra, the use of MS is an ineffective technique to discriminate between these closely related compounds. We set out to determine whether the regioisomers could be differentiated by a combination of GC-MS, acetyl derivatisation and GC-IRD. We demonstrate that the three isomers of methylmethamphetamine and methylamphetamine can be separated by GC, and a combination of acetyl derivatisation and vapour phase IR can identify the specific ring substituted compound.  相似文献   

2.
A fast and efficient procedure has been developed for the analysis of total mercury in human tissues and blood using a hydride vapor generator system coupled to an atomic absorption spectrometer (HVG-AA). Tissue and blood samples were digested in a pressurized microwave decomposition system and the digest diluted prior to formation of free mercury vapor and analysis by atomic absorption. Recovery studies performed on 10 spiked/unspiked pairs of human liver and on 10 spiked/unspiked pairs of human blood samples yielded average recoveries of 99.7% (CV=0.4%) and 101.2% (CV=0.5%), respectively. The method detection limit for liver and blood was 50 microg Hg/kg and 12.5 microg Hg/l, respectively. The "normal" concentrations of mercury in human liver and blood are 33-490 microg Hg/kg and 0.6-59 microg Hg/l, respectively [1]. This method is able to determine mercury poisoning levels and may also be applied to detect mercury near the lower levels of these "normal" ranges, using the standard addition method approach.  相似文献   

3.
Cannabis sativa is both an illegal drug and a legitimate crop. The differentiation of illegal drug Cannabis from non-drug forms of Cannabis is relevant in the context of the growth of fibre and seed oil varieties of Cannabis for commercial purposes. This differentiation is currently determined based on the levels of tetrahydrocannabinol (THC) in adult plants. DNA based methods have the potential to assay Cannabis material unsuitable for analysis using conventional means including seeds, pollen and severely degraded material. The purpose of this research was to develop a single nucleotide polymorphism (SNP) assay for the differentiation of "drug" and "non-drug"Cannabis plants. An assay was developed based on four polymorphisms within a 399 bp fragment of the tetrahydrocannabinolic acid (THCA) synthase gene, utilising the snapshot multiplex kit. This SNP assay was tested on 94 Cannabis plants, which included 10 blind samples, and was able to differentiate between "drug" and "non-drug"Cannabis in all cases, while also differentiating between Cannabis and other species. Non-drug plants were found to be homozygous at the four sites assayed while drug Cannabis plants were either homozygous or heterozygous.  相似文献   

4.
Solid-phase microextraction (SPME) is a new extraction technique with many advantages: small sample volume, simplicity, quickness and solvent-free. It is mainly applied to environmental analysis, but is also useful for the extraction of drugs from biological samples. In this paper the use of SPME is proposed for the determination of methadone and its main metabolite EDDP in hair by GC-MS. The hair samples were washed, cut into 1-mm segments, and incubated with Pronase E for 12 h. A 100-micron polydimethylsiloxane (PDMS) film fibre was submerged for 30 min in a diluted solution of the hydrolysis liquid (1:4 with borax buffer) containing methadone-d3 and EDDP-d3 as internal standards. Once the microextraction was concluded the fibre was directly inserted into the CG injection port. Linearity was found for methadone and EDDP in the range studied, 1.0-50 ng/mg hair, with correlation coefficients higher than 0.99. Interassay relative standard deviation (R.S.D) was determined to be less than 13.30% for methadone and less than 8.94% for EDDP, at 3.0 and 30.0 ng/mg. Analytical recoveries were close to 100% for both compounds on spiked samples. The method was applied to the analysis of real hair samples from eight patients of a methadone maintenance programme. The concentration of methadone in hair ranged from 2.45 to 78.10 ng/mg, and for EDDP from 0.98 to 7.76 ng/mg of hair.  相似文献   

5.
Between 1998 and 2001 the deaths of 16 Surinamese children were recorded along the Maroni River, which forms the border between Suriname and French Guyana. After a metabolic origin was eliminated, ethnobotanical research in the field led to a hypothesis of intoxication through the ingestion of ackee. Ackee (Blighia sapida) is a large green leafy tree of West African origin. Its unripe fruit contains large quantities of two toxic molecules: hypoglycin-A and hypoglycin-B, the former being the more toxic. We have developed a GC-MS procedure allowing us to demonstrate the presence of hypoglycin-A in the gastric fluid of one of the deceased children, and to compare the content of hypoglycin-A in fruit collected on the road to Paramaribo in Suriname (5.1mg/g) with samples from Burkina Faso (8.1mg/g) and Jamaica (9.2mg/g). Field research showed the misuse of this little-known plant by Maroon witch doctors. The Bushinengue witch doctors were informed about the dangers of ackee, and no new cases have been reported to date.  相似文献   

6.
周斌  郭景元 《法医学杂志》1990,6(2):21-26,47
在法医物证检案工作中,经常会遇到ABO型血型的判定,一般通过吸收试验、解离试验、以及混和凝集试验就能够进行分型.但在实际工作中,遇到的检材多数并非单一的体液,而是两种或者两种以上体液的混和斑.特别是强奸案的鉴定,阴道内提取的检材常常是由男性精液和女性阴道分泌物的混合物,要从混和斑中判断各自的血型,目前仍较困难.国内外许多学者都进行了有关的实验,试图  相似文献   

7.
Fatty acid ethyl esters (FAEE) are products of the nonoxidative ethanol metabolism, which are known to be detectable in blood only about 24h after the last alcohol intake. After deposition in hair they should be suitable long-term markers of chronically elevated alcohol consumption. Therefore, a method for the analysis of ethyl myristate, ethyl palmitate, ethyl oleate and ethyl stearate from hair was developed based on the extraction of the hair sample by a dimethylsulphoxide (DMSO)/n-hexane mixture, separation and evaporation of the n-hexane phase and application of headspace solid-phase microextraction (HS-SPME) in combination with gas chromatography-mass spectrometry (GC-MS) to the extract. For use as internal standards, the corresponding D(5)-ethyl esters were prepared. The HS-SPME/GC-MS measurements were automatically performed using a multi-purpose sampler. The detection limits of the FAEE were between 0.01 and 0.04ng/mg and the reproducibility was between 3.5 and 16%. By application of the method to hair samples of 21 fatalities with known heavy alcohol abuse 0.045-2.4ng/mg ethyl myristate, 0.35-13.5ng/mg ethyl palmitate, 0.25-7.7ng/mg ethyl oleate and 0.05-3.85ng/mg ethyl stearate were measured. For social drinkers (30-60g ethanol per week), the concentrations were about one order of magnitude smaller. For 10 teetotalers negative results or traces of ethyl palmitate were found. It was shown by supplementary investigations in single cases that FAEE are also present in sebum, that there is no strong difference in their concentrations between pubic, chest and scalp hair, and that they are detectable in hair segments after a 2 months period of abstinence. From the results follows that the measurement of FAEE concentrations in hair is a useful way for a retrospective detection of alcohol abuse.  相似文献   

8.
An enzyme-linked immunosorbent assay (ELISA) for species identification of human bloodstains using two commercially available antisera against human serum is described. Human bloodstains were to be distinguished from those of chimpanzees and other animals using raw antisera, and the differentiation between human and chimpanzee became more evident when those antisera were absorbed with a small amount of chimpanzee plasma. Human bloodstains could clearly be identified by the present method even after 4 weeks of aging at room temperature.  相似文献   

9.
The objective of this study was to develop a two-step strategy for analysis of opiates and cocaine in hair samples involving an immunological screening procedure followed by confirmation of results using gas chromatography-mass spectrometry (GC-MS). A semi-quantitative automated competitive enzyme-linked immunosorbent assay (ELISA) methodology using Oral Fluid Micro-Plate Enzyme Immunoassays (Orasure Technologies, Inc.) was developed and validated. Applicability was proven by analysis of authentic head hair samples from drug users (n=103) and from opiate associated fatalities (n=21). The optimum cutoff values for the ELISA tests were 0.1 ng cocaine-equivalents/mg hair and 0.05 ng morphine-equivalents/mg hair using a 50 mg hair sample. Both ELISA tests had a sensitivity of 100%, the specificity was 66% for cocaine-equivalents and 42% for morphine-equivalents. The intraassay precision was 11% for the cocaine and 3% for the opiates ELISA, while interassay precision was 12% for the cocaine and 4% for the opiates ELISA test. The actual analyte concentrations in the hair samples were determined using GC-MS and were between 0.04 and 5.20 ng/mg for heroin (HER), between 0.04 and 30.01 ng/mg for 6-monoacetylmorphine (MAM), between 0.03 and 11.87 ng/mg for morphine (MOR), between 0.02 and 1.84 ng/mg for codeine (COD), between 0.02 and 2.48 ng/mg for acetylcodeine (AC), between 0.01 and 21.37 ng/mg for cocaine (COC), between 0.03 and 10.51 ng/mg for benzoylecgonine (BE) and between 0.05 and 1.26 ng/mg for cocaethylene (CE). The automated ELISA tests were proven to be valid screening procedures for the detection of cocaine and opiates in hair as confirmed by GC-MS. Screening methods provide rapid and inexpensive automated pre-test procedures to detect drugs in hair or other matrices. For forensic purposes screening therefore represents an ideal complement to routinely applied GC-MS procedures.  相似文献   

10.
11.
Goldsworth  John 《Trusts & Trustees》2007,13(6):226-227
Trusts set up by will, will trusts, are governed by similarconsiderations to those affecting inter vivos trusts. Frequentlyin trust textbooks the authors do not tell us that will trustshave some significant difference from inter vivos trusts. Thelatter may be set up quite informally by a mere declarationof intention and the transfer of the trust property to the trustees.But will trusts can only come about if the law relating to makinga valid will has been complied with. This tends to get overlookedunder the shadow of possible inheritance tax  相似文献   

12.
A forensiometric model to discriminate between homicidal and suicidal firearm-fatalities is presented. It is based on a survey of all 45 homicidal and 251 suicidal firearm-fatalities that were examined at the Department of Forensic Medicine in Stockholm, Sweden during the period 1983-92. The model used 15 variables to describe 19.8% of the variation in the data and its goodness of prediction, Q2, was 0.742. The variables ranked in falling order of covariation with homicide (i.e. correlation with or importance in the prediction of homicide) were: presence of other injuries than firearm-wounds, entrance wound in the front part of the chest except precordium, bullet path through clothes, entrance wound in upper extremity, female victim, entrance wound in abdomen, entrance wound in head except temples, central forehead and mouth, and entrance wound in back. The variables most correlated to suicide were: used firearm found close to victim's body, reported suicidal ideation, victim's age, presence of contact wound(s), male victim, presence of farewell letter and entrance wound in mouth. The model was thereafter validated on a test-set of 18 homicides and 84 suicides during 1993-95. All suicides and 16 homicides were classified by the model in agreement with the previous police and forensic medical examinations. Thus, the model's sensitivity to classify homicides is estimated to be 89% and its specificity 100%.  相似文献   

13.
14.
The chemical composition of subcutaneous fats was analyzed in a corpse that had died from drowning. The skin of the cadaver examined postmortem showed different stages of adipocere. Samples from these regions were chemically compared with the fatty tissue of a person who had died recently. HPLC, GC, GC-MS, NMR (1H- and 13C-NMR), TLC and titrimetrical methods were used to evaluate the degree of decomposition. The fatty acid pattern of the triglycerides (TG) and the free fatty acids (FFA) obtained by TLC separation was also investigated. Some discrepancy was observed between the autopsy findings and the results of the chemical analysis. It is suggested that the autopsy should be supplemented by chemical analysis in order to describe the state of adipocere correctly.  相似文献   

15.
16.
专家证人辨析   总被引:2,自引:0,他引:2  
夏蔚 《政法学刊》2006,23(6):5-9
在现代诉讼中,专家证人在诉讼证明活动中的作用越来越重要,但我国的证据立法对专家证人的规定却相当滞后,限制了专家证人功能的发挥。对专家证人的资格、专家证人的选定程序、专家证言的可采性审查以及专家证人的民事责任等问题进行研究,有利于完善相关的证据立法,规范专家证人的行为,保护当事人的权益。  相似文献   

17.
目的建立尿液中甲卡西酮的气相色谱-质谱(gas chromatography-mass spectrometry,GC-MS)分析方法。方法在尿液中加入内标双苯戊二氨酯(SKF525A)和pH=9的缓冲溶液,用乙酸乙酯提取,提取液在50℃氮气流下挥干,残余物用甲醇溶解,用GC-MS分析。结果尿液中甲卡西酮在0.02~2.00μg/m L质量浓度范围内线性关系良好,线性方程为y=0.301 9 x+0.018 9(r=0.999 2),检出限为0.01μg/m L。尿液中甲卡西酮回收率为96.4%~99.2%,日内精密度为5.8%~7.6%,日间精密度为6.0%~8.1%。结论该方法操作简便、灵敏度高,可用于司法鉴定实践尿液样品中甲卡西酮的分析。  相似文献   

18.
目的建立苯二氮卓类新精神活性物质去氯依替唑仑的气相色谱-质谱(GC-MS)和超高效液相色谱-四极杆-飞行时间质谱(UPLC-Q-TOF MS)定性检验方法。方法未知样品用甲醇和水提取,取上清液,采用GC-MS和UPLC-Q-TOF MS进行分析。结果经GC-MS检测,保留时间为17.73 min的未知组分的质谱碎片主要特征离子峰有m/z 279,308,239,252,225,77,126。经UPLC-Q-TOF MS检测,保留时间为4.781 min的未知组分的准分子离子峰为309.1173,碰撞诱导解离(CID)模式下二级质谱主要离子有m/z 280.0776,255.0952,240.0719,225.0604,206.0748。经缴获毒品分析科学工作组(Scientific Working Group for the Analysis of Seized Drugs,SWGDRUG)分析谱库检索和文献查询获得的信息资料进行比对,鉴定为去氯依替唑仑。结论该方法具有分析简便、快速的特点,可以用于实际案件的检测。  相似文献   

19.
目的建立血液中双甲脒及其代谢产物单甲脒的气质联用定量检测方法。方法采用液-液萃取前处理,考察了不同的提取溶剂和pH值对检测结果的影响,优化了萃取条件。结果在最优条件下,该方法对双甲脒和单甲脒的检出限分别为2ng/mL和3ng/mL,两种目标物在20~2000ng/mL范围内线性关系良好(砰分别为0.9997和0.9992),血液中双甲脒和单甲脒的回收率为8l%~90%。结论该方法具有良好的灵敏度、重现性、稳定性和专属性,可用于法庭科学与临床学的毒物分析。  相似文献   

20.
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