首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 421 毫秒
1.
Twelve different sets of confiscated ecstasy samples were analysed applying both near infrared spectroscopy in reflectance mode (1100-2500 nm) and high-performance liquid chromatography (HPLC). The sets showed a large variance in composition. A calibration data set was generated based on the theory of factorial designs. It contained 221 N-methyl-3,4-methylenedioxyamphetamine (MDMA) samples, 167 N-ethyl-3,4-methylenedioxyamphetamine (MDE), 111 amphetamine and 106 samples without a controlled substance, which will be called placebo samples thereafter. From this data set, PLS-1 models were calculated and were successfully applied for validation of various external laboratory test sets. The transferability of these results to confiscated tablets is demonstrated here. It is shown that differentiation into placebo, amphetamine and ecstasy samples is possible. Analysis of intact tablets is practicable. However, more reliable results are obtained from pulverised samples. This is due to ill-defined production procedures. The use of mathematically pretreated spectra improves the prediction quality of all the PLS-1 models studied. It is possible to improve discrimination between MDE and MDMA with the help of a second model based on raw spectra. Alternative strategies are briefly discussed.  相似文献   

2.
Cellulose and lactose are the most frequently used excipients in illicit ecstasy production. The aim of this project was to use near infrared reflectance spectroscopy (NIRS) for the determination of the different chemical forms of these two substances, as well as for the differentiation of their origin (producer). It was possible to distinguish between the different chemical forms of both compounds, as well as between their origins (producers), although within limits. Furthermore, the possibilities to apply NIR for the analysis of substances such as found in illicit tablets were studied. First, a few cellulose and lactose samples were chosen to make mixtures with amphetamine at three degrees of purity (5, 10 and 15%), in order to study the resulting changes in the spectra as well as to simultaneously quantify amphetamine and identify the excipient. A PLS2 model could be build to predict concentrations and excipient. Secondarily, the technique was to be applied to real ecstasy tablets. About 40 ecstasy seizures were analysed with the aim to determine the excipient and to check them against each other. Identification of the excipients was not always obvious, especially when more than one excipient were present. However, a comparison between tablets appeared to give groups of similar samples. NIR analysis results in spectra representing the tablet blend as a whole taking into account all absorbing compounds. Although NIRS seems to be an appropriate method for ecstasy profiling, little is known about intra- and intervariability of compression batches.  相似文献   

3.
A solid-phase extraction (SPE) procedure has been developed for impurity profiling of illicit tablets containing 3,4-methylenedioxy-N-methyl-amphetamine (MDMA, ecstasy). Following initial comparison of liquid-liquid extraction and solid-phase extraction, SPE was found to be preferable because it afforded higher extraction efficiencies and shorter extraction times. Procedure blank samples were also analyzed to identify constituents of the extracts which did not originate in the ecstasy tablets. The developed procedure was subsequently applied to 12 samples of seized ecstasy tablets and a comparison was made of these samples to determine similarities and obtain inferences with respect to commonality of origin.  相似文献   

4.
This is the first report on development of a library search‐based screening system for 3,4‐methylenedioxymethamphetamine (MDMA) in ecstasy tablets using a portable near‐infrared (NIR) spectrometer. The spectrum library consisted of spectra originating from standard substances as well as mixtures of MDMA hydrochloride (MDMA‐HCl) and diluents. The raw NIR spectra were mathematically pretreated, and then, a library search was performed using correlation coefficient. To enhance the discrimination ability, the wavelength used for the library search was limited. Mixtures of MDMA‐HCl and diluents were used to decide criteria to judge MDMA‐positive or MDMA‐negative. Confiscated MDMA tablets and medicinal tablets were used for performance check of the criteria. Twenty‐two of 27 MDMA tablets were truly judged as MDMA‐positive. Five false‐negative results may be caused by compounds not included in the library. No false‐positive results were obtained for medicinal tablets. This system will be a useful tool for on‐site screening of MDMA tablets.  相似文献   

5.
In Hong Kong, ecstasy tablets are more commonly known as "Fing Tau Yuen", literally meaning "Shake Head Pills". The tablets contain mainly amphetamine-type stimulants (ATS) including 3,4-methylenedioxymethamphetamine (MDMA), 3,4-methylenedioxyamphetamine (MDA), methamphetamine (MA) and/or ketamine. Adulterant such as caffeine was also detected in the tablets. This paper reports a study on the impurity profiles of ecstasy tablets from 89 seizures in Hong Kong from 2002 to early 2004. Tablet samples were extracted by diethyl ether under alkaline condition and then analyzed by gas GC-MS. The chromatograms obtained were compared. A total of 19 identified impurities were selected as markers for impurity profiling. They are different precursors, intermediates and by-products. The data matrices were examined by hierarchical cluster analysis (HCA), and then the ecstasy tablets were classified into different groups. Cluster analysis of ecstasy tablets is shown to be capable of providing intelligence on clandestine laboratory networks.  相似文献   

6.
During 2000-2001, the Government Laboratory of Hong Kong received over 600,000 ecstasy tablets in more than 2,600 cases. Using GC-MS or FTIR, the major amphetamine-type stimulants were identified, and the samples were categorized into four groups containing: (1) 3,4-methylenedioxymethamphetamine (MDMA), (2) methamphetamine (MA), (3) 3,4-methylenedioxyamphetamine (MDA), or (4) amphetamine. Our study revealed that in Hong Kong MDMA tablets have made up 98 and 71% of the total ecstasy tablets examined in 2000 and 2001, respectively. Among the MDMA cases, 613 cases involving a total of 123,776 tablets in 2001 were randomly selected, and their active ingredients, minor ingredients, and/or impurities were studied using GC-MS and HPLC. Based on the chemical profiles, and irrespective of their different physical characteristics, tablets obtained in different seizures could be determined as to whether or not they could have come from a common origin. The impurities detected in the MDMA tablets also served as excellent chemical markers from which plausible synthetic route(s) of the MDMA were inferred. Our study revealed that 3,4-methylenedioxyphenyl-2-propanone (MDP2P), 3,4-methylenedioxyphenyl-2-propanol (MDP), 3,4-methylenedioxy-N-methylbenzylamine (MDB), piperonal and N-formyl-3,4-methylenedioxymethamphetamine (N-formyl-MDMA) were the most common impurities detected in MDMA tablets seized in Hong Kong. The finding of the phosphate salt of MDMA is intriguing. Based on a presumptive color test, spectroscopic data (FTIR/ESI-MS) and the percentage of MDMA content in a purified phosphate salt of MDMA, the ratio of the phosphate to MDMA was determined to be 1:1, suggesting that the compound is a dihydrogen phosphate salt [i.e. (HMDMA)H2PO4].  相似文献   

7.
The content of ecstasy tablets has been changing over the years, and nowadays 3,4‐methylenedioxymethamphetamine (MDMA) is not always present in the tablets. The aim of this study was to investigate the chemical composition in the seized tablets labeled as ecstasy. We analyzed samples from 150 different seizures made by Sao Paulo's State Police by gas chromatography–mass spectrometry. MDMA was present in 44.7% of the analyzed samples, and another twenty different active substances were identified in these tablets, such as caffeine, 2C‐B, piperazines, amphetamines, phencyclidine, and others. Methamphetamine was present in 22% of these samples. The results demonstrate a huge shift in the pattern of trafficking of synthetic drugs, where MDMA has been replaced in tablets mostly by illicit psychoactive substances, in a clear attempt to bypass the law. The great variability in the tablets composition may lead to an increased risk of drug poisoning.  相似文献   

8.
The variations found in the elemental composition in ecstasy samples result in spectral profiles with useful information for data analysis, and cluster analysis of these profiles can help uncover different categories of the drug. We provide a cluster analysis of ecstasy tablets based on their elemental composition. Twenty‐five elements were determined by ICP‐MS in tablets apprehended by Sao Paulo's State Police, Brazil. We employ the K‐means clustering algorithm along with C4.5 decision tree to help us interpret the clustering results. We found a better number of two clusters within the data, which can refer to the approximated number of sources of the drug which supply the cities of seizures. The C4.5 model was capable of differentiating the ecstasy samples from the two clusters with high prediction accuracy using the leave‐one‐out cross‐validation. The model used only Nd, Ni, and Pb concentration values in the classification of the samples.  相似文献   

9.
This work outlines the unequivocal identification of the "ecstasy" analog, 2-chloro-4,5-methylenedioxymethylamphetamine, using combined gas chromatography/mass spectroscopy (GC/MS) and proton magnetic resonance spectroscopy (1H-NMR). This compound was identified along with 3,4-methylenedioxymethylamphetamine (MDMA) in an illicit tablet seizure, which included 26 off-white tablets.  相似文献   

10.
Sugars and stearates (composed of fatty acids) are both frequent components used in the production of ecstasy tablets. Their analysis can therefore provide supplementary information useful for drug intelligence. Links established using these substances would be very significant as they should give us information about the manufacturer of the tablets. Two methods have been developed for the analysis of sugars and fatty acids by GC-MS and were applied to 109 ecstasy tablets. Characterisation of the samples should allow the differentiation of a certain number of them and furthermore their classification into groups. This is obtained by analysing the raw data using chemometric methods. Several pre-treatments have been tested together with six similarity measures on a small number of ecstasy samples in order to determine which combination would best characterise one ecstasy sample and differentiate it from the others at the same time. Normalisation followed by the fourth square and applied together with the squared cosine function appeared to give the best results and has been applied to all samples. The correlation values obtained of each sample with all others express the probability of a presence of a link between two samples. In order to verify the signification of these values, and thus of a link, all samples have been compared considering the data visually according to three selected criterions. The 109 examined samples could be divided into 67 groups, with 43 of them containing only one sample. Considering the distribution of their correlation values, sample pairs showing a value below 0.23 can be considered as linked. As the excipients are necessarily related to the blending, which also includes the active substance, and variation in the excipient content has been proven by the grouping of the samples, a low similarity value does indicate a link with regard to the producer. In conclusion, it appears that the result obtained with the excipients is certainly very valuable, but all other available information has to be taken into account as well before making any conclusions.  相似文献   

11.
12.
There is an increasing demand for herbal medicines in weight loss treatment. Some synthetic chemicals, such as sibutramine (SB), have been detected as adulterants in herbal formulations. In this study, two strategies using near infrared (NIR) spectroscopy have been developed to evaluate potential adulteration of herbal medicines with SB: a qualitative screening approach and a quantitative methodology based on multivariate calibration. Samples were composed by products commercialized as herbal medicines, as well as by laboratory adulterated samples. Spectra were obtained in the range of 14,000–4000 per cm. Using PLS‐DA, a correct classification of 100% was achieved for the external validation set. In the quantitative approach, the root mean squares error of prediction (RMSEP), for both PLS and MLR models, was 0.2%w/w. The results prove the potential of NIR spectroscopy and multivariate calibration in quantifying sibutramine in adulterated herbal medicines samples.  相似文献   

13.
Drug use histories were collected from 100 subjects recruited from the "dance scene" in and around Glasgow, Scotland. In addition, each subject donated a hair sample which was analyzed by gas chromatography/mass spectrometry (GC/MS) for amphetamine (AP), methamphetamine (MA), 3,4-methylenedioxyamphetamine (MDA), 3,4-methylenedioxymethamphetamine (MD MA) and 3,4-methylenedioxyethylamphetamine (MDEA). The hair samples were analyzed in two 6 cm segments or in full, ranging from 1.5 to 12 cm depending on the length of the hair. Approximately 10 mg of hair was ground to a fine powder before treatment with beta-glucuronidase/aryl sulfatase. A solid-phase extraction procedure was carried out followed by derivatization with pentafluoropropionic anhydride (PFPA). All extracts were analyzed by gas chromatography/mass spectrometry (GC/MS). Of the 139 segments analyzed, 77 (52.5%) were positive for at least one of the five amphetamines. The drug concentrations found in the hair were compared with the self-reported drug histories. A concordance of greater than 50% was found between the self-report data and levels detected in hair. However, no correlation was found between the reported number of "ecstasy" tablets consumed and the drug levels detected in hair. An increase in the average drug levels measured was observed from low to high use (number of "ecstasy" tablets/month). A large number of false negatives and a low number of false positives were observed.  相似文献   

14.
A method for ecstasy volatiles 'signature' analysis based on two-dimensional gas chromatography separation and time-of-flight mass spectrometry detection (GC×GC-TOFMS) is presented. Organic impurity volatiles were extracted by head space solid phase microextraction (HS-SPME). The final column phase choice of the four different column combinations tested was a low-polarity 5% phenyl polysilphenylene-siloxane coupled with a polyethylene glycol phase, which best displayed the complex impurity profile. Second dimension ((2)D) retention time reproducibility was found to be about 1% RSD, and area reproducibility of SPME sampling was just over 5% RSD for compounds with S/N ratio of about 100. High similarity of TOFMS spectra of impurities was obtained against commercial MS libraries. 16 components from the two-dimensional profiles were selected for comparison of the 24 ecstasy tablets, most of which proved to be benzodioxole derived compounds. All tablets were correctly classified in eight groups according to their post-tabletting characteristics, when appropriate data pre-treatment was applied. Principal component analysis revealed clustering of samples according to the country of origin. Samples from Macedonia were elevated in N-formyl-MDMA and N-acetyl-MDMA while samples from Australia were elevated in 3,4-methylenedioxypropane and 3,4-methylenedioxyacetophenone. Furthermore, three components were found to be unique for one of the source countries. The additional separation of components on the (2)D column, increased response due to modulation, high acquisition rate with full mass spectra using TOFMS detection, and MS deconvolution extend the possibility of detecting additional markers and route-specific components, especially of low abundant, polar components.  相似文献   

15.
Identification of 3,4-methylenedioxy-N-methylamphetamine (MDMA, ecstasy) in five cases of intoxication using nuclear magnetic resonance (NMR) spectroscopy of human urine is reported. A new water suppression technique PURGE (Presaturation Utilizing Relaxation Gradients and Echoes) was used. A calibration curve was obtained using spiked samples. The method gave a linear response (correlation coefficient of 0.992) over the range 0.01–1 mg/mL. Subsequently, quantitation of the amount of MDMA present in the samples was performed. The benefit and reliability of NMR investigations of human urine for cases of intoxication with MDMA are discussed.  相似文献   

16.
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   

17.
There is no toxicological analysis of gamma-hydroxybutyrate (GHB) applied routinely in cases of driving under influence (DUI); therefore the extent of consumption of this drug might be underestimated. Its consumption is described as occurring often concurrently with amphetamine or ecstasy. This study examines 196 serum samples which were collected by police during road side testing for GHB. The samples subject to this study have already been found to be positive for amphetamine, methamphetamine, 3,4-methylenedioxyamphetamine (MDA), 3,4-methylenedioxymethamphetamine (MDMA) and/or 3,4-methylenedioxyethamphetamine (MDEA). Analysis has been performed by LC/MS/MS in the multiple reaction monitoring (MRM) mode. Due to its polarity, chromatographic separation of GHB was achieved by a HILIC column. To differentiate endogenous and exogenous levels of GHB, a cut-off concentration of 4μg/ml was applied. Of the 196 samples, two have been found to be positive for GHB. Of these samples, one sample was also positive for amphetamine and one for MDMA. Whilst other amphetamine derivates were not detected in these samples, both samples were found to be positive for cannabinoids. These results suggest that co-consumption of GHB with amphetamine or ecstasy is relatively low (1%) for the collective of this study.  相似文献   

18.
3,4-Methylenedioxymethamphetamine (MDMA) tablets known as "ecstasy" became a very popular drug amongst Israeli youth in the last decade. The ecstasy tablets have a simple design impressed on them (logos) making it relatively easy to distinguish between various logos. The life expectancy of ecstasy tablet logos, defined as the period between the first seizure by the police of a certain logo until the last seizure of the same logo, was monitored during the years 2001-2003. During this time interval, 58 different tablet logos were seized. A total of 26 logos, defined as common logos with at least 10 independent seizures, were observed. At any given time interval during this period, 8-10 common logos were found with an average life expectancy of approximately 9 months. Five of the observed 26 common logos were defined as the most common logos that appeared in at least 200 independent seizures each. Plots of the number of seizures and number of tablets seized as a function of time are presented and discussed as well as explanations for the high turnover rate of any given logo.  相似文献   

19.
This study takes the first step toward in situ analysis of powder drugs which does not require any alteration of the samples. A fast, inexpensive analytical method based on reflectance near-infrared (NIR) spectrometry and multivariate calibration was applied. A diode-array fiber-optic portable spectrometer in the 900-1700 nm range was employed. Samples were laboratory-prepared ternary powders (diacetylmorphine, caffeine, and paracetamol). Partial least squares regression was applied. The choice of the standard samples for calibration and validation was performed through a D-optimal experimental design. The explained variance was higher than 90%, and the relative root mean square errors were <2%. The number of principal components (6) was very low when compared with the number of raw variables (356 absorbance values). Response plots showed slopes and intercepts were very close to optimal values. Correlation coefficients ranged between 0.909 and 0.989. The method here proposed proved to be competitive with Fourier transform NIR spectrometry.  相似文献   

20.
Fatalities due to 3,4-methylenedioxymethamphetamine (MDMA, "ecstasy") are rare in Austria, although the use of designer drugs has become quite common. This is the first published case of a fatal MDMA intoxication in Austria. A 19-year-old girl died after the consumption of ecstasy tablets in the apartment of a friend. Blood analysis gave a concentration of MDMA as 3.8 mg/L and traces of its metabolite MDA. Cannabinoids were found as well. This case shows that the consumption of MDMA, without physical stress, can lead to death.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号