Seized Methamphetamine Samples Research Articles

Characterization of Ephedrine as Illegal Methamphetamine Precursors Based on δ15N, δ13C, and δ2H Isotopes: Their Application for Methamphetamine Profiling in Indonesia

Objectives: The δ15N, δ13C, and δ2H profile of the ephedrine as a methamphetamine precursor is a fingerprint to describing its origin. The origin of the precursor is one of the supporting data in methamphetamine profiling. In this research, the isotope profiles of natural, synthetic, and semi-synthetic clusters of ephedrine were established. These clusters were applied to predict the origin ephedrine from seized methamphetamine samples in Indonesia. Methods: The isotope profiles of methamphetamine and its precursor were clustered in two steps. Initially, ephedrine and pseudoephedrine from various of the origin were prepared, and then the methamphetamines were synthesized from 4 samples ephedrine of known origin using Emde and Moscow routes. Emde is a method mostly found in Indonesia, and also Moscow as a comparison. Elemental Analyzer-IRMS were used to analyze isotope abundance ratio in order to establish the natural, synthetic, and semi-synthetic clusters. This study was carried out to a total of 20 methamphetamine samples to identified the origin of precursors. Results: The results showed that the isotope profiles of ephedrine and pseudoephedrine formed groups based on the origin. And the isotope profiles of methamphetamine were similar to those of the precursors. Conclusion: The δ15N, δ13C, and δ2H isotope clusters of ephedrine/pseudoephedrine can be applied to seized methamphetamine samples to characterize the origin of the precursor.

Recent methamphetamine profiling trends: Tracking the nitrostyrene method used for P2P production

N-butylamphetamine and N-cyclohexylamphetamine have been found to be useful target compounds for tracking P2P-based methamphetamine produced using nitrostyrene chemistry. Since 2015, these two process impurities have been detected at low levels in many seized methamphetamine samples and forensic information regarding these target compounds is provided in this report. Several laboratory experiments were performed using a variety of nitrostyrene related conditions to synthesize P2P. Methamphetamine was then produced using standard reductive amination conditions to prove that the presented target impurities were detected and therefore related to nitrostyrene chemistry. Methamphetamine profiling data is then presented to show that nitrostyrene related profiles have been dominant in the United States for the last 3 years.

Simultaneous chiral analysis of amphetamine-type stimulants and ephedrine by capillary electrophoresis coupled to time-of-flight mass spectrometry.

This study focused on the chiral characteristics of methamphetamine seizures in Shanghai for inferring the synthetic pathways of drugs. Capillary electrophoresis coupled to time-of-flight mass spectrometry was used for simultaneous chiral separation of amphetamine-type stimulants and ephedrine, including S(+)-amphetamine/R(-)-amphetamine, S(+)-methamphetamine/R(-)-methamphetamine, (±)-MDA (3,4-methylenedioxyamphetamine), (±)-MDMA (3,4-methylenedioxymethamphetamine), (±)-MDEA (3,4-methylenedioxy-N-ethylamphetamine), d,l-N-ethylamphetamine, methylephedrine/methylpseudoephedrine, and 1S,2R(+)-ephedrine/(-)-ephedrine. The running buffer was 50-mM ammonium formate (pH2.2 was adjusted by 1-M formic acid) containing 0.26% highly sulfated γ-cyclodextrin as the chiral selector. All enantiomers were well resolved within 40minutes by capillary electrophoresis at 20kV in an uncoated fused-silica capillary (50-μm I.D.×375-μm O.D.×90-cm length) and detected by micro time-of-flight mass spectrometry. Twenty seized methamphetamine samples were determined by the established method. They were classified into two groups through their chiral characteristics.

Carbon and Nitrogen Stable Isotope Analyses of Ephedra Plant and Ephedrine Samples and Their Application For Methamphetamine Profiling.

In this study, stable isotope ratio analysis was used to track the precursor information of methamphetamine. The δ13 C and δ15 N values of 30 nature ephedra plants, 12 synthetic ephedrine/pseudoephedrine (ephedrine), 14 natural ephedrine, and 987 seized methamphetamine samples were measured and compared. Due to different weather and earth conditions, the δ13 C and δ15 N values of ephedra plants grown in the east and the west of Inner Mongolia showed great difference. The δ15 N values of ephedra plants were consistent with related ephedrine extracted from them. Moreover, the criteria to infer the synthetic origin of ephedrine were set up after the analysis of natural and synthetic ephedrine samples. Finally, the precursor origins of 949 seized methamphetamine samples synthesized by Emde and Nagai method were tentatively inferred. Influenced by different preprecursors, the δ13 C values of seized methamphetamine samples that synthesized from P2P also showed great difference, and this result is consistent with the reported data.

The use of a sulfonated capillary on chiral capillary electrophoresis/mass spectrometry of amphetamine-type stimulants for methamphetamine impurity profiling

Chiral capillary electrophoresis/tandem mass spectrometry (CE/MS/MS) using a chemically modified capillary containing sulfonated groups was developed for the following 8 amphetamine-type stimulants (ATS): amphetamine, methamphetamine (MA), norephedrine, norpseudoephedrine, ephedrine (EP), pseudoephedrine (pEP), dimethylamphetamine and methylephedrine. The running buffer was 10mM formic acid containing 20mM highly sulfated γ-cyclodextrin (pH 2.5) as the chiral selector. All 16 enantiomers were well resolved within 60min, and precisely identified due to their characteristic mass spectra. Further, the RSDs of the migration times of the analytes were no more than 0.3% without any standardization. (1R,2S)-(−)-EP and (1S,2S)-(+)-pEP, which are important ATS impurities originating in the precursors, were added to a highly concentrated MA solution (1mg/mL) and analyzed as mock samples for MA impurity analysis. Acceptable repeatability of the migration times of (−)-EP and (+)-pEP (ca. 0.3% RSDs) was still observed without interference from the large amount of MA. The limits of detection (LOD) of (−)-EP and (+)-pEP were approximately 2μg/mL, therefore, their LOD as the impurity concentrations were calculated at about 0.2%. Seized MA samples were dissolved in water at a high concentration (1mg/mL) and analyzed by this method. (−)-EP and (+)-pEP were clearly detected as impurities. Although these compounds had similar migration times and mass spectral patterns, the fine repeatability allowed easy identification of the impurities by a simple comparison of the absolute migration times of the specimens and those of authentic standards. This study is the first to report the use of a chemically modified capillary for the impurity profiling on CE/MS/MS.

Development of an automated data processing method for sample to sample comparison of seized methamphetamines

The information about the sources of supply, trafficking routes, distribution patterns and conspiracy links can be obtained from methamphetamine profiling. The precursor and synthetic method for the clandestine manufacture can be estimated from the analysis of minor impurities contained in methamphetamine. Also, the similarity between samples can be evaluated using the peaks that appear in chromatograms. In South Korea, methamphetamine was the most popular drug but the total seized amount of methamphetamine whole through the country was very small. Therefore, it would be more important to find the links between samples than the other uses of methamphetamine profiling. Many Asian countries including Japan and South Korea have been using the method developed by National Research Institute of Police Science of Japan. The method used gas chromatography-flame ionization detector (GC-FID), DB-5 column and four internal standards. It was developed to increase the amount of impurities and minimize the amount of methamphetamine. After GC-FID analysis, the raw data have to be processed. The data processing steps are very complex and require a lot of time and effort. In this study, Microsoft Visual Basic Application (VBA) modules were developed to handle these data processing steps. This module collected the results from the data into an Excel file and then corrected the retention time shift and response deviation generated from the sample preparation and instruments analysis. The developed modules were tested for their performance using 10 samples from 5 different cases. The processed results were analyzed with Pearson correlation coefficient for similarity assessment and the correlation coefficient of the two samples from the same case was more than 0.99. When the modules were applied to 131 seized methamphetamine samples, four samples from two different cases were found to have the common origin and the chromatograms of the four samples were appeared visually identical. The developed VBA modules could process raw data of GC-FID very quickly and easily. Also, they could assess the similarity between samples by peak pattern recognition using whole peaks without spectral identification of each peak that appeared in the chromatogram. The results collectively suggest that the modules would be useful tools to augment similarity assessment between seized methamphetamine samples.

Seized methamphetamine samples with unique profiles of stable nitrogen isotopic composition documented by stable isotope ratio mass spectrometry

We report a case of seized methamphetamine (MA) samples showing unique profiles of stable isotopic compositions. Three packages of MA-HCl samples seized simultaneously from one suspect were subjected to gas chromatographic impurity profiling and stable isotope ratio mass spectrometry (IRMS). The samples showed similar impurity profiles by gas chromatography, but their stable isotopic compositions were complicated. The δ15N values of the samples from each package varied widely when the crystals were analyzed separately; we could differentiate two major groups labeled I and II, and also their subgroups. Each of the three packages contained MA-HCl crystals belonging to multiple groups and subgroups. It was considered that several batches of MA-HCl with starting materials from different sources were mixed together after a similar or the same synthesis procedure and then divided into the packages. This is the first report to show that stable IRMS is useful for differentiating seized MA using small crystals from different sources.

The impurity characteristics of methamphetamine synthesized by Emde and Nagai method

Impurity profiling and classification of seized methamphetamine may play an important role in the interpretation of analytical results, the determination of the synthetic method employed, and the criminal investigations of drug traffic routes. Our study is focused on classifying seized methamphetamine samples according to the groups sorted by the types and quantities of impurities present in illicit methamphetamine samples. The samples (100 mg) were dissolved in 2 mL of potassium phosphate buffer (pH 7.0), extracted with 200 μL of ethyl acetate under basic condition, and then analyzed by gas chromatography-mass spectrometry (GC–MS) with a DB-1 capillary column (30 m × 0.25 mm i.d., 0.25 μm). Five impurities are used as criteria for the classification of seized methamphetamine samples by Emde and Nagai method. A total of fifty-two samples of seized methamphetamine were analyzed by GC–MS and classified by five organic impurities, and then sorted into four groups, which are Nagai type, Emde Type, Undetermined I type, and Undetermined II type.

Analysis of inorganic impurities in seized methamphetamine samples

Classification of seized methamphetamine by impurity profiling can provide very useful information on drug intelligence. In this report, the validity of inorganic impurity analysis in discriminating seized methamphetamine samples in Japan was investigated using inductively coupled plasma mass spectrometry (ICP-MS) and atomic absorption spectrometry (AAS). Triplicate sampling was carried out on 17 methamphetamine samples seized in Japan. About 20 mg of methamphetamine was taken, and was dissolved in 20 ml of water. After the qualitative analysis, Ba, Sb, Pd, Sr, Br, Zn and Cu were determined by ICP-MS, and Na was determined by AAS. Among eight elements determined in this study, most cations showed large heterogeneity in their content. On the other hand, the contents of Na which is abundant in methamphetamine samples, showed relatively small intra-sample variation, and that of Br also showed good homogeneity. On the basis of the concentration of Br and Na, 17 seized methamphetamine samples were classified into five groups. Trace elements such as Tl, Hg, Au or Cs were qualitatively detected by ICP-MS. These elements can provide useful information to impurity profiling of seized methamphetamine, because these elements are characteristically present in each sample. Application of ICP-MS and AAS to the analysis of inorganic impurities can be helpful in giving additional information to the impurity profiling of seized methamphetamine by organic impurity analysis.