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11.
Heroin samples, seized from the North Korean merchant vessel Pong Su in Australian waters, were analyzed to determine geographic origin. Duplicate samples were analyzed by the National Measurement Institute's Australian Forensic Drug Laboratory and the United States Drug Enforcement Administration's Special Testing and Research Laboratory. Alkaloid ratios were determined by both liquid chromatography-diode array detection (LC-DAD) and capillary electrophoresis-diode array detection (CE-DAD) techniques. Acid/neutral manufacturing by-products were determined by solvent extraction followed by gas chromatography-mass spectrometry (GC-MS). Solvents, trapped in the heroin particles during manufacture, were detected by both static headspace GC-MS and purge and trap GC-MS. The alkaloid ratios obtained were consistent with heroin of a Southeast Asian (SEA) origin and principal component analysis of the alkaloid results demonstrated the presence of at least four subgroupings within the seizure. The solvent analysis detected diethyl ether and ethyl acetate, solvents typically seen in SEA heroin. However, the acid/neutral analysis revealed compounds not normally seen in heroin of a SEA origin. Furthermore, sterol-like molecules, always detected in the acid/neutral analysis of SEA heroin, were absent from the Pong Su samples. The Pong Su heroin, although similar to SEA heroin, has sufficient differences to classify it as having an unknown origin at the time of this writing.  相似文献   
12.
The forensic application of stable isotope analysis to cocaine and heroin for geolocation of exhibits must take into account the possible enrichment and/or depletion of 13C and 15N during the illicit manufacturing process. Continuous-flow elemental analysis-isotope ratio mass spectrometry was utilized to measure changes in the stable isotope ratios of carbon and nitrogen for both cocaine (N = 92) and heroin/morphine (N = 81) exhibits derived from illicit manufacturing processes utilized by South American clandestine chemists. In controlled settings in South America, there was no siginficiant carbon isotope fractionation during the conversion of cocaine base to cocaine HCI using current illict methodologies. In contrast, nitrogen isotope fractionation for this conversion was 1 per thousand. There was a kinetic carbon isotope ratio fractionation during the acetylation of Colombian morphine to heroin and as a result heroin exhibits will almost always have more negative delta13C values than the original morphine. There was an isotopic fractionation against 15N during the acetylation of morphine base to heroin base, but this effect was not expressed since all of the heroin base was precipitated during the manufacturing process. However, the clandestine process of converting a single batch of heroin base usually involved two consecutive crops of heroin HCl and the latter crop was isotopically depleted as expected from a Rayleigh distillation process. When heroin was deacetylated to morphine, the morphine produced resulted in delta13C values that were indistinguishable from the original morphine. The kinetic carbon isotope fractionation factor for the South American process of morphine acetylation was -1.8 per thousand, allowing calculation of the delta13C values of the acetic anhydride from deacetylated heroin delta13C values.  相似文献   
13.
Alkaloid extracts from the seeds of Erythroxylum Coca var. Coca grown in the Chapare Valley of Bolivia were subjected to gas and liquid chromatographic-mass spectrometric analyses. Several alkaloids from these seeds were detected and characterized, including methylecgonidine, tropine, 3alpha-acetoxytropane, ecgonine methyl ester, cuscohygrine, N-norbenzoyltropine, benzoyltropine, hexanoylecgonine methyl ester, cocaine, cis-cinnamoylcocaine, and trans-cinnamoylcocaine. Methylecgonidine was determined to be the primary constituent and not an analytical artifact. Additionally, two significant new uncharacterized alkaloids were established as present. Recent evidence suggests that some cocaine processors are adding this seed extraction material to cocaine extracted from coca leaf and may impact cocaine impurity signature profiles.  相似文献   
14.
Abstract:  The illicit manufacture of heroin results in the formation of trace level acidic and neutral impurities. These impurities are detectable in illicit heroin and provide valuable information about the manufacturing process used. The isolation, derivatization, and semiquantitative analysis of neutral and acidic heroin manufacturing impurities by programmed temperature vaporizing injector-gas chromatography-mass spectrometry (PTV-GC-MS) is described. Trace acidic and neutral heroin impurities were isolated from basic fractions using liquid–liquid extraction. Extracted impurities were treated with N -Methyl- N -trimethylsilyltrifluoroacetamide followed by PTV-GC-MS analyses. Semiquantitative data were obtained using full scan mass spectrometry utilizing unique ions or ion combinations for 36 trace impurities found in crude and/or highly refined heroin samples. Minimum detection limits for acidic and neutral impurities were estimated to be at the 10−7 level relative to total morphine. Over 500 authentic heroin samples from South America, Mexico, Southwest Asia, and Southeast Asia were analyzed. Classification of illicit heroin based on the presence or absence and relative amounts of acidic and neutral impurities is presented.  相似文献   
15.
For nearly 30 years, the methods utilized in illicit cocaine hydrochloride production have remained relatively consistent. Cocaine hydrochloride is typically produced one kilogram at a time. As a result, each individual kilogram is unique and distinct from other kilograms in any particular seizure based on the total alkaloid profile, occluded solvent profile, and isotopic signature. Additionally, multi-kilogram cocaine seizures are often comprised of cocaine from several different coca growing regions. There has been a documented shift in this type of processing based on the recent analysis of a large cocaine seizure in the Eastern Pacific. Signature analyses of samples from 21 kg randomly selected from a 517 kg seizure were virtually identical. Triplicate analyses of each sample via gas chromatography with flame ionization detection, static headspace gas chromatography mass spectrometry, and isotope ratio mass spectrometry were completed. An initial outlier evaluation of the data and an in-depth univariate analysis indicated there was no statistically significant difference among the 21 samples at the 95% confidence interval. Principal components analysis did reveal consistent minor deviations between the samples and known authentic data from the Nariño coca growing region of Colombia. These deviations were only observed on the latter principal components and could be explained by differences in solvent selection during cocaine hydrochloride processing. Chemical analyses in addition to a thorough statistical evaluation suggest a shift in the traditional small-batch method of cocaine processing to a multi-kilogram, high throughput approach.  相似文献   
16.
A new type of heroin HCl seized in Australia was examined by stable isotope analysis. The final origin/process classification of these samples by chromatographic signature profiles of the impurity/manufacturing by-products was previously determined to be "unknown" by two independent national laboratories. Various drug enforcement authorities speculated that the heroin might be from a new region or new illicit process due to the unusual chromatographic impurity profiles that were present. Samples from 20 different kilogram packages were examined for isotopic content to determine if the samples fit isotopic patterns of known origins or if they were unique to any known origins. Authentic specimens from Southeast Asian (N=59), Southwest Asia (N=37), South America (N=104), and Mexico (N=21) we concomitantly examined for comparison purposes. Both continuous flow elemental analysis-isotope ratio mass spectrometry and gas chromatography-isotope ratio mass spectrometry techniques were utilized. Heroin samples were also converted to morphine, without apparent isotopic fractionation, utilizing methanolic HCl for gas chromatography-isotope ratio mass spectrometry. The Pong Su samples were found to be isotopically and isotopically/alkaloidally distinct from the known origin/process classifications of Southwest Asian, Southeast Asian, South American, and Mexican.  相似文献   
17.
The current clandestine methodology for the manufacture of illicit cocaine hydrochloride utilizes microwave heating in order to dry the finished product. This study addresses the effects this step has on the occluded solvents present in newly prepared cocaine hydrochloride. Nine 1-kilogram-sized batches of cocaine hydrochloride were prepared from cocaine base using a variety of solvents or solvent mixtures commonly utilized in clandestine laboratories, pressed into bricks, and submitted to microwave heating. Residual solvents were qualitatively and quantitatively monitored before, during, and following the microwaving step by static headspace-gas chromatography-mass spectrometry. All solvents used in the conversion process were easily detected in the bricks even after extensive irradiation, confirming that occluded solvents are extremely resistant to removal by microwave heating. Qualitative and quantitative data corresponding to the residual solvents in the prepared cocaine hydrochloride bricks are presented.  相似文献   
18.
Measurements were made on the natural abundance (14)C content (Δ(14)C) of cocaine specimens seized between 2003 and 2009. The objective of this study was to determine the extent to which Δ(14)C analyses could quantify the "age" of recent cocaine seizures. Here "age" of a seized cocaine specimen is defined as the time period between when a coca leaf was harvested in South America and its seizure as cocaine at either the international or domestic street levels. Based on Δ(14)C analyses of seizure specimens, there were no statistically significant differences in the ages of domestic cocaine HCl and cocaine base specimens seized on the streets in different locations across the United States. Between 2007 and 2009, the average age of a street-level cocaine seizure in the United States was 24.6±1.1 months. Cocaine shipment seizures that were in excess of 150 kg during this time period had an average age of 18.2±1.4 months, whereas smaller shipment seizures were significantly older with an average age of 22.3±0.6 months. Analyses of the largest cocaine shipment seizures suggested that these seizures were composed of specimens with different ages, possibly representing accumulations over as much as a 31-month period.  相似文献   
19.
We describe a case of factitious disorder with physical and psychological symptoms comorbid with bipolar I disorder in a 37-year-old woman. Since the onset of bipolar disorder, which occurred at the age of 31, she increasingly complained of physical symptoms, compulsively seeking medical and surgical interventions. She has been hospitalised several times and her Munchausen-type factitious disorder recently appeared to be developing into Munchausen by proxy, involving her 11-year-old daughter. The patient adhered poorly to stabilising and antipsychotic drug treatment and did not improve through the years. We here analyse her mood phases, which were always associated with changes in the quality of factitious symptoms, according to whether the disorder was in its depressive phase (somatic complaints and suicidal ideation prevail), or in its manic or mixed phase (medical intervention-seeking and manipulation of clinicians to obtain surgical interventions). We also briefly discuss some important forensic issues to consider in similar cases, mainly stemming from the psychotic aspects of these two co-occurring disorders. Clinicians should be aware of some patients' ability to produce signs and symptoms of physical and/or psychological illness and consult psychiatrists before giving consent to invasive diagnostic procedures or surgery.  相似文献   
20.
Seven ethyl homologues of known tropane esters have recently been detected as impurities in the gas chromatographic signature profiles of authentic Peruvian illicit cocaine base and hydrochloride exhibits. Peruvian cocaine base processors are now known to use ethanol for the purification of crude cocaine base. This process is referred to as the "base lavada" or "washed base" process and is a recent substitute method for the potassium permanganate oxidation purification methodology. Seven ethyl ester homologues were formed in illicit cocaine from the transesterification of known tropane methyl esters or possibly ethyl esterification of their respective tropane C-2 carboxylic acids in the presence of ethanol. Exhibits containing these compounds were subjected to gas chromatographic-mass spectrometric analyses to determine their identity and were subsequently synthesized to verify their structures. Quantitative determinations were obtained from ion-pair chromatography isolation followed by gas chromatography with flame ionization detection. Specifically, hexanoylecgonine ethyl ester, cocaethylene, cis-cinnamoylecgonine ethyl ester, trans-cinnamoylecgonine ethyl ester, 3',4',5'-trimethoxybenzoylecgonine ethyl ester, cis-3',4',5'-trimethoxycinnamoylecgonine ethyl ester, and trans-3',4',5'-trimethoxycinnamoylecgonine ethyl ester were detected and characterized. When present, these compounds were detected at levels ranging from 8.6 x 10(-4) to 9.3 x 10(-1)% relative to cocaine.  相似文献   
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