Effect of Extraction Procedure and Gas Chromatography Temperature Program on Discrimination of MDMA Exhibits

Analysis of impurities in seized MDMA tablets can be used to determine the synthesis method used and to identify links among exhibits. However, no standardized method exists to generate impurity profiles, limiting comparisons among different laboratories. This research investigated the effect of extraction procedure and gas chromatography temperature program on the resulting impurity profiles. Five exhibits were extracted using liquid–liquid extraction (LLE) and headspace solid‐phase microextraction (HS‐SPME), then analyzed using two different temperature programs. Profiles were statistically assessed using principal components analysis. While LLE was more reproducible, more compounds were extracted using HS‐SPME, thus providing more informative chemical profiles. The longer temperature program (53 min vs. 36 min) allowed greater discrimination of exhibits, due to improved precision as a result of an extended hold time (12 min). This research further highlights the need for standardized extraction and analysis procedures to allow comparison of chemical profiles generated in different laboratories.     

Comparison and classification of methamphetamine seized in Japan and Thailand using gas chromatography with liquid-liquid extraction and solid-phase microextraction

Methamphetamine (MA) is one of the most frequently abused drugs worldwide. The aim of this study is to improve the analytical method for profiling MA impurity in order to compare and classify MA crystals seized in different countries and to investigate the relationships between seizures. To compare MA samples seized in Japan and Thailand, the following analytical method was adopted. A 50mg sample of MA.HCl was dissolved in 1ml of buffer solution (four parts 0.1M phosphate buffer, pH 7.0, and one part 10% Na(2)CO(3)), impurities were extracted with 0.5ml of ethyl acetate containing four internal standards (n-decane, n-pentadecane, n-eicosane and n-octacosane) and analyzed by gas chromatography with a flame ionization detector on a DB-5 capillary column (0.32mm i.d.x30m, film thickness 1.0mum). Fourteen characteristic peaks on chromatograms were selected for the comparison and classification of samples, and the data were evaluated by the Euclidean distance of the relative peak areas after logarithmic transformation. Sixty-nine samples seized in Japan and 42 seized in Thailand were analyzed. The samples were classified into four groups roughly by cluster analysis. In addition, when it was difficult to compare samples that had fewer impurities on chromatograms obtained from liquid-liquid extraction (LLE), solid-phase microextraction (SPME) was effective. Because many characteristic peaks were detected using SPME, SPME made it easy to compare samples of high purity. The combination of LLE and SPME was useful for impurity profiling of MA samples seized in different countries.     

Evaluation of a Headspace Solid‐Phase Microextraction Method for the Analysis of Ignitable Liquids in Fire Debris

The chemical analysis of fire debris represents a crucial part in fire investigations to determine the cause of a fire. A headspace solid‐phase microextraction (HS‐SPME) procedure for the detection of ignitable liquids in fire debris using a fiber coated with a mixture of three different sorbent materials (Divinylbenzene/Carboxen/Polydimethylsiloxane, DVB/CAR/PDMS) is described. Gasoline and diesel fuel were spiked upon a preburnt matrix (wood charcoal), extracted and concentrated with HS‐SPME and then analyzed with gas chromatography/mass spectrometry (GC/MS). The experimental conditions—extraction temperature, incubation and exposure time—were optimized. To assess the applicability of the method, fire debris samples were prepared in the smoke density chamber (SDC) and a controlled‐atmosphere cone calorimeter. The developed methods were successfully applied to burnt particleboard and carpet samples. The results demonstrate that the procedure that has been developed here is suitable for detecting these ignitable liquids in highly burnt debris.     

Chemical profiling of 3,4-methylenedioxymethamphetamine (MDMA) tablets seized in Hong Kong

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].     

Solid-phase extraction for profiling of ecstasy tablets

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.     

Analysis of Ecstasy Tablets Using Capillary Electrophoresis with Capacitively Coupled Contactless Conductivity Detection

A method for the identification of 3,4‐methylenedioxymethamphetamine (MDMA) and meta‐chlorophenylpiperazine (mCPP) was developed employing capillary electrophoresis (CE) with capacitively coupled contactless conductivity detection (C⁴D). Sample extraction, separation, and detection of “Ecstasy” tablets were performed in <10 min without sample derivatization. The separation electrolyte was 20 mm TAPS/Lithium, pH 8.7. Average minimal detectable amounts for MDMA and mCPP were 0.04 mg/tablet, several orders of magnitude lower than the minimum amount encountered in a tablet. Seven different Ecstasy tablets seized in Rio de Janeiro, Brazil, were analyzed by CE‐C⁴D and compared against routine gas chromatography‐mass spectrometry (GC‐MS). The CE method demonstrated sufficient selectivity to discriminate the two target drugs, MDMA and mCPP, from the other drugs present in seizures, namely amphepramone, fenproporex, caffeine, lidocaine, and cocaine. Separation was performed in <90 sec. The advantages of using C⁴D instead of traditional CE‐UV methods for in‐field analysis are also discussed.     

A contribution to the chemical profiling of 3,4-methylenedioxymethamphetamine (MDMA) tablets

A profiling method for the identification of impurities found in seized 3,4-methylenedioxymethamphetamine (MDMA) tablets is presented. Impurities of interest are extracted from an alkaline solution (pH 12.8) by diethyl ether and submitted to gas chromatography (GC)-mass spectrometry (MS) analyses. Identification of impurities is performed by electron impact ionization (Ei) mass spectrometry and confirmation by positive chemical ionization (Ci+) MS or, when possible, MS/MS (MS(2)). Repeat extractions of the same sample give an average relative standard deviation (R.S.D.) of less than 8% within the same day and 15% between days (results were obtained after normalization by the sum of peak areas, each one being acquired by selected ion monitoring (SIM)). Possible application toward batch comparison of samples is discussed. Chromatographic profiles are compared using the cosine function for evaluating similarity and/or dissimilarity among exhibits.     

Cross-examination of liquid-liquid extraction (LLE) and solid-phase microextraction (SPME) methods for impurity profiling of methamphetamine

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.     

The Variability of Ecstasy Tablets Composition in Brazil

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.     

Development of a Library Search‐Based Screening System for 3,4‐Methylenedioxymethamphetamine in Ecstasy Tablets Using a Portable Near‐Infrared Spectrometer

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.     

Screening tablets for DOB using surface-enhanced Raman spectroscopy

2,5,-Dimethoxy-4-bromoamphetamine (DOB) is of particular interest among the various "ecstasy" variants because there is an unusually long delay between consumption and effect, which dramatically increases the danger of accidental overdose in users. Screening for DOB in tablets is problematic because it is pharmacologically active at 0.2-3 mg, which is c. 50 times less than 3,4-methylenedioxy-N-methylamphetamine (MDMA) and makes it more difficult to detect in seized tablets using conventional spot tests. The normal Raman spectra of seized DOB tablets are dominated by the bands of the excipient with no evidence of the drug component. Here we report the first use of on-tablet surface-enhanced Raman spectroscopy (SERS) to enhance the signal from a low concentration drug. Raman studies (785-nm excitation) were carried on series of model DOB/lactose tablets (total mass c. 400 mg) containing between 1 mg and 15 microg of DOB and on seized DOB tablets. To generate surface-enhanced spectra, 5 microL of centrifuged silver colloid was dispensed onto the upper surface of the tablets, followed by 5 microL of 1.0 mol/dm(3) NaCl. The probe laser was directed onto the treated area and spectra accumulated for c. 20 sec (10 sec x 2). It was found that the enhancement of the DOB component in the model tablets containing 1 mg DOB/tablet and in the seized tablets tested was so large that their spectra were completely dominated by the vibrational bands of DOB with little or no contribution from the unenhanced lactose excipient. Indeed, the most intense DOB band was visible even in tablets containing just 15 microg of the drug. On-tablet surface-enhanced Raman spectroscopy is a simple method to distinguish between low dose DOB tablets and those with no active constituent. The fact that unique spectra are obtained allows identification of the drug while the lack of sample preparation and short signal accumulation times mean that the entire test can be carried out in <1 min.     

Availability of target odor compounds from seized ecstasy tablets for canine detection

The aim of this study was to compare seized samples of 3,4-methylenedioxy-N-methylamphetamine (MDMA) pills, used to train law enforcement detection canine teams, to determine what differences exist in the chemical makeup and headspace odor and their effect on detectability. MDMA solutions were analyzed by liquid chromatography-mass spectrometry. Analysis of these samples showed a wide variance of MDMA (8-25%). Headspace SPME-GC/MS analysis showed that several compounds such as 3,4-methylenedioxyphenylacetone and 1-(3,4-methylenedioxyphenyl)-2-propanol are common among these MDMA samples regardless of starting compound and synthesis procedure. However, differences, such as the level of the various methylenedioxy starting compounds, were shown to affect the overall outcome of canine detection, indicating the need for more than one MDMA training aid. Combinations of compounds such as the primary odor piperonal in conjunction with a secondary compound such as MDP-2-OH or isosafrole are recommended to maximize detection of different illicit MDMA samples.     

Contribution of thermal desorption and liquid-liquid extraction for identification and profiling of impurities in methamphetamine by gas chromatography-mass spectrometry

Impurity profiling of methamphetamine (MA) using thermal desorption (TD) and gas chromatography-mass spectrometry (GC-MS) was examined. Using TD/GC-MS, impurities were extracted and separated under various conditions. Optimal chromatograms were obtained when a 20 mg MA sample was extracted at 120 degrees C for 3 min using a TD instrument, followed by separation of the extracts using a non-polar capillary column coated with (5%phenyl)-methylpolysiloxane. MA samples from nine different batches were analyzed under optimized conditions. Compounds related to the structure of MA, such as benzaldehyde, benzyl alcohol, amphetamine, cis- and trans-1,2-dimethyl-3-phenylaziridine, dimethylamphetamine, and N-acetylephedrine, were detected in the chromatograms without any laborious extraction procedure. Compounds such as ethanol, diethyl ether, and acetic acid, which are considered reagents and solvents for MA synthesis, were also detected in some of the chromatograms. The numbers and intensities of the peaks detected were different among the samples. Impurity profiling of MA using TD was compared with that using liquid-liquid extraction (LLE). Better reproducibility of peak areas was obtained using LLE, whereas higher intensities and numbers of peaks were detected using TD. Solvents were extracted more effectively using TD. The nine batches of MA were classified using both extraction procedures. The nine batches were divided roughly into two groups using data from LLE. Subsequently, the groups were classified in detail using data from TD. TD can be used to provide supplemental information for LLE, and the combination of these extraction methods can be helpful for impurity profiling of MA.     

Characteristics and trends of 3,4-methylenedioxymethamphetamine (MDMA) tablets found in Taiwan from 2002 to February 2005

One hundred and eighty-one 3,4-methylenedioxymethamphetamine (MDMA) containing tablets were sampled from confiscated drugs received by the Taiwan National Bureau of Controlled Drugs for testing from 2002 to February 2005. Sample tablets demonstrated various colors and logos. The appearances, contents of MDMA and other components in these tablets were analyzed in order to understand the characteristics and trends of MDMA use. Samples were analyzed using GC-MS methodology. Deuterated internal standards were used for drug quantification. The MDMA contents varied from 16 to 193 mg/tablet. 66-71% of the tablets seized each year contained only MDMA, and the content of MDMA in MDMA only tablets varied from 89 to 133 mg/tablet. There was a decreasing trend in MDMA content in these tablets over time. Other components commonly found besides MDMA included caffeine (18%), methamphetamine (7%), 3,4-methylenedioxyethylamphetamine (MDEA) (7%) and amphetamine (4%). 3,4-Methylenedioxyamphetamine (MDA), ketamine, ephedrine, diazepam, chlorzoxazone and nicotinamide were also detected. During the study period, the number of other drugs found as well as the combinations of different drugs detected in these tablets increased.     

Seizures of Clandestinely Produced Tablets in Santa Catarina,Brazil: The Increase in NPS from 2011 to 2017

Ecstasy is the name given to a large group of substances known as “club drugs” traded in the form of tablets, powder and liquid that present a varied composition, including mainly 3,4-methylenedioxymethamphetamine (MDMA) and analogous substances, in addition to the growing presence of new psychoactive substances. Based on this, clandestinely produced tablets (“ecstasy tablets”) seized by police in Santa Catarina in the period from 2011 to 2017 were analyzed. During the study period, 3472 seizures occurred, which resulted in total 498,443 tablets seized. Seventy nine substances were identified. In the year 2011, about 90% of the tablets contained MDMA. This number decreased to 66.6% in 2017. On the other hand, there was an increase in the number of tablets that mainly contained synthetic cathinones, as well as tryptamine and piperazine derivatives. Police seizures in the metropolitan region of Florianópolis and on the coast prevailed over the rest of the state.     

Organic impurity profiling of 3,4-methylenedioxymethamphetamine (MDMA) tablets seized in The Netherlands.

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.     

Comparative Analysis of the Chemical Profiles of 3,4-Methylenedioxymethamphetamine Based on Comprehensive Two-Dimensional Gas Chromatography-Time-of-Flight Mass Spectrometry (GC × GC-TOFMS)*

Abstract: The chemical profiling of illicit drugs is an important analytical tool to support the work of investigating and law enforcement authorities. In our work, comprehensive two‐dimensional gas chromatography–time‐of‐flight mass spectrometry (GC × GC‐TOFMS) combined with nontargeted, pixel‐based data analysis was adapted for the chemical profiling of 3,4‐methylenedioxymethamphetamine (MDMA). The validity and benefit of this approach was evaluated by analyzing a well‐investigated set of MDMA samples. Samples were prepared according to a harmonized extraction protocol to ensure the comparability of the chemical signatures. The nontargeted approach comprises preprocessing followed by analysis of variances as a fast filter algorithm for selection of a variable subset followed by partial least squares discriminant analysis for reduction to promising marker compounds for discrimination of the samples according to their chemical profile. Forty‐seven potential marker compounds were determined, covering most of the target impurities known from the harmonized one‐dimensional profiling as well as other compounds not previously elucidated.     

生物检材中甲基苯丙胺及苯丙胺的分析研究进展

对近几年国内外22篇有关生物检材中甲基苯丙胺及苯丙胺测定的文献进行了综述。介绍了血、尿、毛发等生物检材的收集与预处理方法,比较了生物检材中甲基苯丙胺及苯丙胺的液-液萃取(LLE)、固相萃取(SPE)、固相微萃取(SPME)和顶空固相微萃取(HS-SPME)等提取方法,以及内标的选取、不同的衍生化方法和包括免疫、GC/MS、GC/NPD、GC/ECD、GC/FID、HPLC、HPCE在内的各种检测方法。最后,对分析结果的评定进行了讨论。     

Detection of Cutting Agents in Drug‐Positive Seized Exhibits within the United States

The following report summarizes a study performed on seized drug exhibits collected in two U.S. states to evaluate the presence and identification of cutting agents. Aliquots of seized drug materials from Kentucky (n = 200) and Vermont (n = 315) were prepared using a dilute‐and‐shoot procedure. Initial analysis was performed using gas chromatography–mass spectrometry (GC‐MS) followed by analysis using liquid chromatography quadrupole time‐of‐flight mass spectrometry (LC‐QTOF). Active compounds detected overall included caffeine (31.0%), quinine/quinidine (24.7%), levamisole (11.6%), acetaminophen, (8.2%) and procaine (8.2%). These compounds were found with several drugs of abuse, such as heroin, fentanyl, methamphetamine, and cocaine. This novel information about cutting agents used to dilute or alter drugs of abuse is important to criminal investigations and in the management of acute intoxications at health centers. However, common methodologies for analysis and standard reporting practices frequently do not include cutting agents, resulting in lacking or inadequate information regarding prevalence of these substances.     

体液中常见滥用药物的系统筛选分析

本文建立了体液中常见滥用药物的筛选分析体系.尿液或血液经固相萃取(SPE)或液提取(LLE)后,直接用GC/NPD分析或经TFA、BSTFA衍生化后用GC/MS分析.方法适用于同时分析甲基苯丙胺、MDMA、度冷丁、去甲度冷丁、曲马多、美沙酮、EDDP、可卡因、苯甲酰芽子碱、可待因、安定、氯丙嗪、吗啡、单乙酰吗啡等十四种常见滥用药物及代谢物.SPE法和LLE法回收率分别为66～102%和50～86%,最低检出限为2-5ng/ml尿.涉毒案件的鉴定应用表明该分析方法简便、快速、可靠.