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1.
Heroin impurity profiling: trends throughout a decade of experimenting.   总被引:3,自引:0,他引:3  
Heroin is still one of the most frequently abused drugs of today. All over the world, law enforcement agencies try to eradicate the illicit production and trafficking of this potent and highly addictive narcotic. To this aim, important information is provided by physical and chemical toxicological analysis of confiscated samples, with special attention for the identification and the quantification of minor components, such as the impurities related to the origin and manufacturing. By combining these data complex characterisations, i.e. impurity profiles, chemical signatures or fingerprints, can be obtained and used for comparative analysis. This review focuses on heroin impurity profiling during the 1990s, proclaimed by the United Nations as the 'Decade for Eradicating Drug Abuse'. Special attention will be given to the new trends in analytical techniques as well as in data handling strategies, so called chemometrics, to produce these profiles. The latter can be used in comparative analysis of seized heroin samples for tactical (batch-to-batch comparison) and strategic (origin determination) intelligence purposes.  相似文献   

2.
Profiling illicit ecstasy tablets has the potential to become an invaluable tool in the crackdown on drug trafficking, but that potential has yet to be fully realized. The impurity profile of an ecstasy tablet can be used to determine the method employed to synthesize the actual controlled substance, which in most cases, is 3,4-methylenedioxymethamphetamine (MDMA). Tablets can then be linked to a common synthetic route, potentially to a common manufacturer, and possibly even to a common manufacturing batch, based on the impurities present. Current methods for profiling MDMA tablets typically involve extracting the organic impurities for analysis by gas chromatography-mass spectrometry. The potential of profiling the trace metals present in tablets has begun to be investigated while more robust statistical and chemometric procedures are being applied to compare and link tablets. This article reviews the recent advances in MDMA impurity profiling from 2002 up to the end of 2006.  相似文献   

3.
Classification of seized methamphetamine by impurity profiling can provide very useful information in criminal investigations of drug traffic routes, sources of supply and relationships between seizures. The aim of this study is to improve and develop an analytical method for detecting impurities such as starting materials and by-products in illegally prepared methamphetamine.HCl samples. A 50mg sample of methamphetamine.HCl was dissolved in 1 ml of buffer solution (four parts 0.1M phosphate buffer pH 7.0 and one part 10% Na2CO3). Impurities were extracted with 0.5 ml of ethyl acetate containing four internal standards (ISs) (n-decane, n-pentadecane, n-nonadecane and n-hexacosane) and analyzed by gas chromatography (GC) using a flame ionization detector (FID) on a DB-5 capillary column (0.32 mmi.d. x 30 m, film thickness 1.0 microm). The use of a middle-bore column offered better separation of the impurity peaks. The correction of the retention times of impurity peaks with four ISs made peak identification very accurate for subsequent data processing. Twenty-four characteristic peaks were selected for comparison and similarity and/or dissimilarity between samples, and the data were evaluated by the Euclidean distance of the relative peak areas after logarithmic transformation. The results indicate that the present method would be useful for methamphetamine impurity profiling.  相似文献   

4.
A pilot study was undertaken to evaluate DNA profiling of the bacterial community in soil as an alternative to geological methods for forensic soil comparisons. Soil samples from three different ecosystems were compared, and the variation within and between ecologically different sites was determined by using terminal restriction fragment (TRF) analysis of 16S ribosomal DNA. Comparison of TRF profiles revealed that samples from within a specific ecosystem (e.g., a field) showed a significantly higher similarity to each other than to those from another ecosystem (e.g., a forest). In addition, some profile features were unique to specific ecosystems. These features may allow the determination of characteristic profiles that will facilitate identification of ecologically different sites, so that a given sample collected from a suspect could be identified as originating from, for example, a field, rather than a forest. The implications of these preliminary findings for forensic investigations are discussed.  相似文献   

5.
Fetal death has been defined by the World Health Organization as death before complete expulsion or extraction from its mother of a product of conception, irrespective of the duration of pregnancy. Certain causes of fetal death, including syphilis, Rh isoimmunization, toxemia, and diabetes, have shown significant declines over the past several decades. However, many fetal losses continue to occur from intrauterine infections, lethal malformations, fetal growth retardation, and abruptio placentae. Fetal death with no identifiable specific cause is another consideration when dealing with these cases. Other risk factors can include maternal, sociodemographic, and medical care factors. The authors reviewed all forensic cases referred for autopsy to the Forensic Section of the Medical University of South Carolina, Medical Examiners' Office over the 10-year period 1990-1999. All cases listed as fetal death or stillbirth were included. The 42 cases were analyzed as to fetus' gestational age, sex, race, weight, location of delivery, history of prenatal care, maternal drug use, chromosomal abnormalities, cause and manner of death, and autopsy findings. The black:white ratio was approximately 2:1, and the male:female ratio was virtually 1:1. Most fetuses were older than 20 weeks' gestational age, with one third between 20 and 29 weeks. The majority were externally normal aside from maceration. Only 7.5% had congenital anomalies. Twenty-one of 38 placentas were grossly and microscopically normal. Of cases with toxicologic analysis, 21% were positive for drugs, and 17% were positive for cocaine/benzoylecgonine. The manner of death was classified as natural (28), accident (2), and undetermined (12). Few studies have reported the specific causes of fetal death, and the lack of uniformity in data collection and classification of causes of fetal death has made comparisons difficult. The authors present this retrospective study to better determine the factors leading to fetal demise in the hope of assisting death investigators in this challenging arena.  相似文献   

6.
In this study, a new method was developed for the impurity profiling of illicit MDMA tablets. The extraction efficiency, linearity, repeatability and reproducibility of the method were evaluated. Eighty two MDMA tablets coming from presumed unrelated large seizures in 2004 (n >500 tablets) were analyzed by gas chromatography mass spectrometry (GC-MS) in order to assess the discrimination power of the method. The latter was found to be practical, robust, relatively easy to perform, highly discriminative and yielding good chromatography. In addition, some new impurities were detected and identified. Their chemical structures and mass spectra are reported.  相似文献   

7.
Abstract: Organic impurity profiling of seized 3,4‐methylenedioxymethamphetamine (MDMA) tablets aims to link tablets to common production sources. Conventionally, organic impurities are extracted from tablets using a liquid–liquid extraction (LLE) procedure prior to analysis by gas chromatography–mass spectrometry (GC‐MS). In this research, the development of an alternative microwave‐assisted extraction/headspace solid‐phase microextraction (MAE/HS‐SPME) procedure is described. The optimal procedure used phosphate buffer (1 M, pH 8), with an HS‐SPME extraction temperature of 70°C for 40 min, using a divinylbenzene/Carboxen?/polydimethylsiloxane (DVB/CAR/PDMS) fiber. Impurities were extracted from seized MDMA exhibits using the MAE/HS‐SPME procedure, as well as HS‐SPME alone, and a conventional LLE procedure. The HS‐SPME procedure was deemed to be the most practical because of the affordability and need for less analyst involvement. Although the LLE was limited in the number of impurities extracted, the procedure is still useful for the extraction of less volatile impurities that are not extracted by HS‐SPME.  相似文献   

8.
9.
Gas chromatography (GC) and gas chromatography/mass spectrometry (GC/MS) are commonly used for the impurity profiling of illegal drugs. For the impurity profiling of methamphetamine, it is very important to obtain information about impurities related to the manufacturing route and the precursor chemicals [B. Remberg, A.H. Stead, Drug characterization/impurity profiling, with special focus on methamphetamine: recent work of the United Nations International Drug Control Programme, Bull. Narcotics LI (1999) 97-117 ]. There are many artifact impurities arising from the preparation of samples and conditions of GC. Moreover, some impurities pose a barrier to the statistical processing of methamphetamine profiling. We investigated capillary GC analysis using pulsed splitless (PS/L) injection to minimize the thermal decomposition of impurities at the injection port and improve the transfer of samples into the column. We confirmed that the optimal conditions of PS/L-mode are 230 degrees C (injection temperature), 50 psi (pulsed pressure) and 1.1 min (pulsed time) for the methamphetamine profiling. Based on the impurity profiles of 48 methamphetamine crystals in PS/L-mode, we can achieve very easy handling and obtained, good results.  相似文献   

10.
The National Institute of Forensic Toxicology, Oslo, receives blood and urine samples from all Norwegian drivers apprehended on suspicion of driving under the influence of alcohol or drugs. In 1983 we received samples from 1446 drug-suspected drivers, out of which 445 underwent toxicological analysis. The drugs found most frequently were tetrahydrocannabinol (THC) (n = 199), diazepam (n = 166) and amphetamine (n = 102). A cautious interpretation of the data indicate that about 200 of the 445 subjects selected for toxicological analysis drove under severe influence of drugs. Because of the high percentage of submitted cases not analysed for drugs, this figure represents a minimum estimate. Compared with the results from 1978, we found a several-fold increase in detections of THC and amphetamine in 1983. The number of diazepam detections did not increase in a similar way, but we estimated that the diazepam detections would have increased 3-fold if we had analysed as frequent for this drug in 1983 as in 1978.  相似文献   

11.
12.
Impurities in 48 methamphetamine (MA) samples were analyzed by liquid-liquid extraction (LLE) and headspace solid-phase microextraction (HS-SPME) methods. MPS-2 autosampler was used to improve reproducibility of SPME method, and nonadecane (C(19)) diluted with potassium bromide (KBr) powder was used as an internal standard for standardizing retention time. Impurities identified by SPME method showed different patterns compared with LLE method. Non-volatile impurities like methamphetamine dimer were not identified by SPME method, but some volatile impurities like diphenylketone, caprolactam and lots of unknowns were identified only by SPME method. 1-Phenyl-2-propanone (P2P), 1-phenyl-2-propanol and benzylcyanide peaks could be discriminated clearly by SPME method without interference of amphetamine, an artifact originates from MA degradation. Differences in the impurity patterns resulted in different clustering results. When 48 MA samples were classified into 5 LLE and 5 SPME clusters, cross-matching of the clusters resulted in 8 sub-clusters. It shows that combination of the different extraction methods can distinguish the differences which cannot be distinguished by LLE or SPME method alone, and can improve reliability of the profiling results.  相似文献   

13.
Only a small fraction of sudden unexpected deaths are caused by neoplastic disease and thus subject ot medicolegal autopsy. The medicolegal autopsy forms an opportunity to study not only medically diagnosed and treated neoplasms, but also the natural evolution of untreated disease. In a series of 7,020 consecutive medicolegal autopsies in northern Sweden, we found 171 cases with malignant and/or intracranial neoplasms. In 41 cases, sudden death was caused by previously unknown tumors. The most common mechanisms of death in this group were disseminated cancer, intracranial tumors, pulmonary thromboembolism, hemoptysis, and aspiration of blood, and the most common locations were the bronchi and the lung. In some of these cases, the mechanism was sometimes dramatic, raising a question of violent death or intoxication. In 30 cases, sudden unexpected death was caused by previously known tumors, and also in this group disseminated cancer was the most common cause of death, and the most common locations were the bronchi and the lung. In 22 cases, tumors were found suicidal cases; in 14 of these, the tumor was considered to be a major causative factor to the suicide, while in eight cases the tumor was considered to be an incidental finding. The expected number of cancers in the 1,060 suicides investigated in this series was 27, according to the official cancer prevalence data. Thus, a possible over-representation of suicides among persons with cancer seems doubtful and needs further exploration.  相似文献   

14.
A retrospective study of 84 cases of suicidal hanging was undertaken in which petechial haemorrhages or congestion were seen in 27%, soft tissue haemorrhage in 29% and fracture of the hyoid or laryngeal cartilages in 36%. Fractures were found to be related to increasing age and were not found when a soft ligature had been employed. Petechial haemorrhages and congestion were related to the completeness of suspension. Apart from the lack of fractures in the soft ligature group any of these findings, either singly or in combination, was found to occur without regard to age, suspension type or ligature type. No evidence was found of clustering or seasonality. The findings are compared to other series and discussed with regard to the mechanisms of causation.  相似文献   

15.
Amphetamine-type substances (ATS), like other synthetically derived compounds, can be produced by a multitude of synthetic pathways using a variety of precursors and reagents, resulting in a large number of possible contaminants (by-products, intermediates and impurities). This review article describes the common contaminants found in preparations of methylamphetamine (MA), 3,4-methylenedioxymethylamphetamine (MDMA), amphetamine (AP), N,N-dimethylamphetamine (DMA) and p-methoxyamphetamine (PMA) synthesised via common synthetic pathways including reductive amination, Leuckart method, Nagai method, Emde method, Birch reduction, “Moscow” method, Wacker process, “Nitrostyrene” method and the Peracid oxidation method.Contaminants can facilitate identification of the synthetic route, origin of precursors and may suggest information as to the location of manufacture of these illicit drugs. Contaminant profiling can provide vital intelligence for investigations in which linking seizures or identifying the synthetic pathway is essential. This review article presents an accessible resource; a compilation of contaminants resulting from a variety of manufacturing methods used to synthesise the most common ATS. It is important for research in this field to continue as valuable information can be extracted from illicit drug samples, increasing discrimination amongst ATS, and in turn, leading to an increase in evidential value and forensic drug intelligence from forensic drug samples.  相似文献   

16.
Abstract: This paper reports the results of a commission to develop a field deployable rapid short tandem repeat (STR)‐based DNA profiling system to enable discrimination between tissues derived from a small number of individuals. Speed was achieved by truncation of sample preparation and field deployability by use of an Agilent 2100 BioanalyserTM. Human blood and tissues were stabbed with heated stainless steel wire and the resulting sample dehydrated with isopropanol prior to direct addition to a PCR. Choice of a polymerase tolerant of tissue residues and cycles of amplification appropriate for the amount of template expected yielded useful profiles with a custom‐designed quintuplex primer set suitable for use with the BioanalyserTM. Samples stored on wires remained amplifiable for months, allowing their transportation unrefrigerated from remote locations to a laboratory for analysis using AmpFlSTR® Profiler Plus® without further processing. The field system meets the requirements for discrimination of samples from small sets and retains access to full STR profiling when required.  相似文献   

17.
Child death due to repeated episodes of physical assault or neglect has been termed the child abuse-maltreatment syndrome (CAMS). We characterized the injuries in a series of fatally abused or maltreated child to delineate objective diagnostic criteria for the CAMS for use by clinicians and pathologists. All deaths (age <17 years) investigated by the Office of the Chief Coroner for Ontario, Canada during the time period 1990-1995 were reviewed. Cases of CAMS were defined as death due to lethal recent injury or malnutrition in the presence of significant old (healing or healed) injuries indicative of repeated episode of inflicted trauma. The nature and frequency of the various injuries was determined. The frequency of the shaken baby syndrome, and the types and frequency of ano-genital injuries were also studied. Twenty-one cases of fatal CAMS were found in the study period. Most cases had significant recent head injury with intra-cranial hemorrhage (71%). Other significant recent injuries commonly observed included blunt injuries of the skin and soft tissues (67%), blunt abdominal trauma with visceral injuries (14%), and fractures (18%). Eight cases (38%) fulfilled accepted criteria for the shaken baby syndrome. Many children with fatal head injuries had evidence of older head trauma (38% of all cases). A significant minority of cases had evidence of malnutrition due to neglect (10%) or ongoing ano-genital injuries (10%). Most cases of child homicides due to repeated episodes of abuse or maltreatment involve head trauma including shaken baby syndrome. Fractures of long bone and ribs, the classical markers of child abuse, were relatively infrequent compared with head injury. A proportion of cases had ano-genital injuries due to repeated sexual abuse or punitive maltreatment. All clinicians and pathologists must recognize the wide spectrum of injuries in child abuse to ultimate protect the victim or other children in an at-risk situation.  相似文献   

18.
He BF  Lou DD 《法医学杂志》2006,22(2):156-158
降解生物检材遗传标记的检测一直是法医学实践和科研的难点。虽然PCR-STR分析技术能在一定程度上检测降解生物检材的遗传标记,但是对于某些高度降解的生物检材如骨骼、牙齿等的PCR-STR分型仍旧十分困难,存在不稳定性和分型异常现象。本文就近几年来PCR-STR分型技术在降解生物检材的法医实践中出现的问题和解决方法作一综述。  相似文献   

19.
More than 3 million children are abused and/or neglected each year in the United States. Unfortunately, a significant percentage of these cases result in homicide by child abuse or child neglect. Causes of death range from blunt force trauma and shaking to asphyxia to immolation. We retrospectively reviewed all pediatric forensic cases referred to the Medical University of South Carolina Forensic Pathology Section over the past 10 years, from January 1986 to December 1995. Of these, we looked only at children < or =5 years of age. The majority (342 cases, 69%) of these deaths were classified as natural, 96 (19%) as accident, and 60 (12%) as homicide. Of the homicides, we examined the cause of death; age, gender, and race of the victim; relationship to the perpetrator; time interval between injury and death; and the initial history given as to the cause of the injury. The cause of death fell into nine categories, the number one category being head trauma. Forty-five percent of the homicides were by head trauma, 12% by abdominal or body trauma, 25% by asphyxia (with half of these due to drowning), 10% by carbon monoxide poisoning or thermal injury, and the remaining 8% involving cases of neglect, stabbing, and poisoning. The majority of the homicide victims were male (67%) and black (67%). Forty-six percent were < or =1 year of age. Approximately 25% of the homicide cases were designated as shaken baby syndrome (SBS). In 97% of the cases, the assailant was known to the victim and was a family relative in 77%. Sixty-three percent of the assailants were female and 45% of the assailants were male; in 12%, the assailants were both parents, and in 1 case, the assailant remains unknown. Of the asphyxia deaths, 87% of the assailants were female. The time interval between injury and death ranged from minutes to hours in most cases to months in cases of repeated abuse and chronic injury and sequelae. The time interval between injury and the onset of symptoms remains unknown in most cases due to inconsistencies in the history and lack of credibility of the caretaker. The most common initial history given was "a fall" (20%). We report our findings of a decade of pediatric homicides to increase awareness of the common scenarios and case histories, demographics of the victims, causes of death, and perpetrators of pediatric homicide.  相似文献   

20.
We describe a novel method for rapidly identifying and distinguishing between different DNA sequences using short tandem repeat (STR) analysis and DNA microarrays. The method can be used to deduce identity, length, and number of STRs of the target molecule. We refer to this technique as the "variable-length probe array" method for STR profiling (VLPA). The method involves hybridization of the unknown STR target sequence to a DNA microarray displaying complementary probes that vary in length to cover the range of possible STRs. A post-hybridization enzymatic digestion of the DNA hybrids is then used to selectively remove labeled single-stranded regions of DNA from the microarray surface. The number of repeats in the unknown target is then deduced based on the pattern of target DNA that remains hybridized to the array. This DNA profiling technique is useful for performing forensic analysis to uniquely identify individual humans or other species.  相似文献   

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