Rapid and simple method for direct determination of several amphetamines in seized tablets by GC--FID

A simple and rapid method for direct simultaneous determination of amphetamine, methamphetamine, 3,4-methylenedioxyamphetamine (MDA), 3,4-methylenedioxymethamphetamine (MDMA), 3,4-methylenedioxy-N-ethylamphetamine (MDEA) and N-methyl-1-(3,4-methylenedioxyphenyl)-2-butanamine (MBDB) in seized tablets was developed using gas chromatography with flame ionization detection. Separation of all six underivatized amphetamines, including diphenylamine as internal standard, was performed in about 6 min, using SPB-50 capillary column. Amphetamine and methamphetamine eluted with negligible tailing while the other amphetamines had highly symmetrical peaks. Sensitivity per component on-column was in the nanogram range, and reproducibility from 2.6 to 6.6% at low concentration (2.4 microg/mL) and from 1.2 to 2.6% at high (70 microg/mL) concentration. The method has a wide linear range, from Limit of detection (LOD) to almost 200 microg/mL, thus allowing analysis of different samples across a wide range of possible concentrations of amphetamines. This simple, fast and precise method using gas chromatography--flame ionization detector (GC--FID), in conjunction with other methods (TLC, IR, HPLC), can be used for identification of amphetamines and direct determination in seized tablets, especially in laboratories with heavy workload.     

Fast LC-MS/MS method for the determination of amphetamine, methamphetamine, MDA, MDMA, MDEA, MBDB and PMA in urine

A fast method was designed for the simultaneous determination of amphetamine (A), methamphetamine (MA), PMA, MDA, MDMA, MDEA and MBDB in urine. The drugs were analysed by LC (ESI)-MS/MS, after a simple liquid-liquid extraction in the presence of the deuterated analogues. Reverse phase separation on an Atlantis dC18 Intelligent Speed column was achieved in less than 4 min under gradient conditions, and the total run time was 8 min. The method was fully validated, including linearity (1-1000 ng/mL for A, MDMA, MDEA and MBDB; 2-1000 ng/mL for MDA and PMA; 1-200 ng/mL for MA; r2>0.99 for all compounds), recovery (>80%), within-day and between-day precision and accuracy (CV and MRE<12.7% for intermediate level and ULOQ, and <17.2% for LLOQ), limit of detection (0.2 ng/mL for MDMA, MDEA and MBDB; 0.5 ng/mL for A, MA and PMA; 1 ng/mL for MDA) and quantitation (1 ng/mL for A, MA, MDMA, MDEA and MBDB; 2 ng/mL for MDA and PMA) and relative ion intensities. No matrix effect was observed. The procedure proved to be sensitive, specific and rapid, and was applied to real forensic cases.     

Quantitative determination of amphetamines, cocaine, and opiates in human hair by gas chromatography/mass spectrometry

Hair of young subjects (N = 36) suspected for drug abuse was analysed for morphine, codeine, heroin, 6-acetylmorphine, cocaine, methadone, amphetamine, methamphetamine, 3,4-methylenedioxyamphetamine (MDA), 3,4-methylenedioxymethamphetamine (MDMA), and 3,4-methylenedioxyethylamphetamine (MDEA). The analysis of morphine, codeine, heroin, 6-acetylmorphine, cocaine, and methadone in hair included incubation in methanol, solid-phase extraction, derivatisation by the mixture of propionic acid anhydride and pyridine, and gas chromatography/mass spectrometry (GC/MS). For amphetamine, methamphetamine, MDA, MDMA, and MDEA analysis, hair samples were incubated in 1M sodium hydroxide, extracted with ethyl acetate, derivatised with heptafluorobutyric acid anhydride (HFBA), and assayed by GC/MS. The methods were reproducible (R.S.D. = 5.0-16.1%), accurate (85.1-100.6%), and sensitive (LoD = 0.05-0.30ng/mg). The applied methods confirmed consumption of heroin in 18 subjects based on positive 6-acetylmorphine. Among these 18 heroin consumers, methadone was found in four, MDMA in two, and cocaine in two subjects. Cocaine only was present in two, methadone only in two, methamphetamine only in two, and MDMA only in seven of the 36 subjects. In two out of nine coloured and bleached hair samples, no drug was found. Despite the small number of subjects, this study has been able to indicate the trend in drug abuse among young people in Croatia.     

Prevalence of gamma-hydroxybutyrate (GHB) in serum samples of amphetamine, metamphetamine and ecstasy impaired drivers

Two hundred and forty-seven serum samples which have been collected by police during roadside testing and have been found positive for amphetamine, methamphetamine, 3,4-methylenedioxyamphetamine (MDA), 3,4-methylenedioxymethamphetamine (MDMA) and/or 3,4-methylenedioxyethamphetamine (MDE) were analyzed for gamma-hydroxybutyrate (GHB). Serum samples were spiked with deuterated GHB as internal standard and acetonitrile was added to achieve dilution and protein precipitation. Samples were analyzed with a LC-MS/MS system operated in the multiple reaction monitoring mode (MRM) using a TurboIonSpray source. Chromatographic separation was achieved using a Synergi Polar RP column applying a gradient elution with a runtime of 15 min. To differentiate between endogenous and exogenously administered GHB a cut-off concentration of 10 microg/mL was applied. Five samples exceeded this concentration and were found positive for GHB. These samples were only found positive for amphetamine but no other amphetamine derivatives were detected, while in three samples THC and in one sample cocaine, benzoylecgonine and ethanol were found.     

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.     

Application of solvent microextraction to the analysis of amphetamines and phencyclidine in urine

A fast and simple method to detect some commonly abused illicit drugs, amphetamine, methamphetamine, 3,4-methylendioxy-amphetamine (MDA), 3,4-methylendioxy-methamphetamine (MDMA), 3,4-methylendioxy-N-ethylamphetamine (MDEA) and phencyclidine (PCP) in urine using solvent microextraction (SME) combined with gas chromatography (GC) analysis has been developed. The extraction is conducted by suspending a 2 microl drop of chloroform in a 2 ml urine sample. Following 8 min of extraction, the organic solvent is withdrawn into the syringe and injected into a GC with a pulsed discharge helium ionization detector (PDHID). The effects of different extraction solvents and times, pH and sample preparation were studied. The optimized method was capable of detecting drugs in urine at concentrations below Substance Abuse and Mental Health Services Administration (SAMHSA) established cut-off values for preliminary testing. Good linearity and reproducibility of extraction were obtained. The limits of detection were 0.5 microg/ml for amphetamine, 0.1 microg/ml for methamphetamine and MDA, 0.05 microg/ml for MDMA, 0.025 microg/ml for MDEA and 0.015 microg/ml for PCP. Relative standard deviation (R.S.D.) values ranged between 5 and 20% for the studied drugs.     

The designer drug situation in Ibiza

A total of 137 urine samples and 46 serum samples, corresponding to 154 self-confessed designer drugs consumers in Ibiza island, were analyzed for the presence of designer drugs: amphetamine and amphetamine derivatives (methamphetamine, methylenedioxymethamphetamine (MDMA), methylenedioxyethylamphetamine (MDEA), methylenedioxyamphetamine (MDA), p-methoxymethylamphetamine (PMMA), p-methoxyamphetamine (PMA), etc.), ketamine and γ-hydroxybutyric acid. Among this population, coming both from the forensic clinic and from the emergency room of a hospital, a total of 99 cases were found positive for some designer drug. This study shows the prevalence of methylenedioxymethamphetamine (MDMA) among designer drug users, sole or in association with other drugs. Also, the mixture of MDMA with other designer drugs, ethanol and/or cocaine is shown to be more likely to produce toxic symptoms requiring clinical attendance in a hospital emergency room. These findings along with the consumption history, the concentrations of drugs and metabolites in urine and serum and the toxicological significance for the interpretation of some MDMA metabolites such as 4-hydroxy-3-methoxymethamphetamine (HMMA) are discussed in this study.     

Application of solvent microextraction to the analysis of amphetamines and phencyclidine in urine

A fast and simple method to detect some commonly abused illicit drugs, amphetamine, methamphetamine, 3,4-methylendioxy-amphetamine (MDA), 3,4-methylendioxy-methamphetamine (MDMA), 3,4-methylendioxy-N-ethylamphetamine (MDEA) and phencyclidine (PCP) in urine using solvent microextraction (SME) combined with gas chromatography (GC) analysis has been developed. The extraction is conducted by suspending a 2 μl drop of chloroform in a 2 ml urine sample. Following 8 min of extraction, the organic solvent is withdrawn into the syringe and injected into a GC with a pulsed discharge helium ionization detector (PDHID).The effects of different extraction solvents and times, pH and sample preparation were studied. The optimized method was capable of detecting drugs in urine at concentrations below Substance Abuse and Mental Health Services Administration (SAMHSA) established cut-off values for preliminary testing. Good linearity and reproducibility of extraction were obtained. The limits of detection were 0.5 μg/ml for amphetamine, 0.1 μg/ml for methamphetamine and MDA, 0.05 μg/ml for MDMA, 0.025 μg/ml for MDEA and 0.015 μg/ml for PCP. Relative standard deviation (R.S.D.) values ranged between 5 and 20% for the studied drugs.     

Simultaneous analysis of six amphetamines and analogues in hair, blood and urine by LC-ESI-MS/MS. Application to the determination of MDMA after low ecstasy intake

A rapid and sensitive method using LC-MS/MS triple stage quadrupole for the determination of traces of amphetamine (AP), methamphetamine (MA), 3,4-methylenedioxyamphetamine (MDA), 3,4-methylenedioxymethamphetamine (MDMA, "ecstasy"), 3,4-methylenedioxyethamphetamine (MDEA), and N-methyl-1-(3,4-methylenedioxyphenyl)-2-butanamine (MBDB) in hair, blood and urine has been developed and validated. Chromatography was carried out on an Uptisphere ODB C(18) 5 microm, 2.1 mm x 150 mm column (Interchim, France) with a gradient of acetonitrile and formate 2 mM pH 3.0 buffer. Urine and blood were extracted with Toxitube A (Varian, France). Segmented scalp hair was treated by incubation 15 min at 80 degrees C in NaOH 1M before liquid-liquid extraction with hexane/ethyl acetate (2/1, v/v). The limits of quantification (LOQ) in blood and urine were at 0.1 ng/mL for all analytes. In hair, LOQ was <5 pg/mg for MA, MDMA, MDEA and MBDB, at 14.7 pg/mg for AP and 15.7 pg/mg for MDA. Calibration curves were linear in the range 0.1-50 ng/mL in blood and urine; in the range 5-500 pg/mg for MA, MDMA, MDEA and MBDB, and 20-500 pg/mg for AP and MDA. Inter-day precisions were <13% for all analytes in all matrices. Accuracy was <20% in blood and urine at 1 and 50 ng/mL and <10% in hair at 20 and 250 pg/mg. This method was applied to the determination of MDMA in a forensic case of single administration of ecstasy to a 16-year-old female without her knowledge during a party. She suffered from hyperactivity, sweating and agitation. A first sample of urine was collected a few hours after (T+12h) and tested positive to amphetamines by immunoassay by a clinical laboratory. Blood and urine were sampled for forensic purposes at day 8 (D+8) and scalp hair at day 60 (D+60). No MDMA was detected in blood, but urine and hair were tested positive, respectively at 0.42 ng/mL and at 22 pg/mg in hair only in the segment corresponding to the period of the offence, while no MDA was detectable. This method allows the detection of MDMA up to 8 days in urine after single intake.     

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.     

Simultaneous analysis of amphetamine, methamphetamine, and 3, 4-methylenedioxymethamphetamine (MDMA) in urine samples by solid-phase extraction, derivatization, and gas chromatography/mass spectrometry

A rapid and effective solid-phase extraction procedure using Bond Elute Certify bonded silica sorbent cartridges was adopted to extract amphetamine, methamphetamine, and 3,4-methylenedioxymethamphetamine (MDMA or Ecstasy) from urine samples. The extract was derivatized with trichloroacetic anhydride prior to gas chromatography/mass spectrometry (GC/MS) analysis with selected ion monitoring of the following ions: 190, 91, 188; 204, 91, 202; 162, 135, 202; 194, 123; and 211, 209 for the derivatized amphetamine, methamphetamine, MDMA, d5-amphetamine, and d9-methamphetamine, respectively. The first of the ions listed for each compound was used for quantitation. The compound d5-amphetamine was used as the internal standard for amphetamine, and d9-methamphetamine was used for methamphetamine and MDMA. Results showed a higher than 65% recovery and a reproducibility with less than a 5% coefficient of variation. When a sample size of 2 mL was used, the lowest detectable concentration was about 50 ng/mL, and a near-perfect fit can be obtained (within the 250 to 4000-ng/mL concentration range studied) using a second-order polynomial model.     

The designer drug situation in Ibiza

A total of 137 urine samples and 46 serum samples, corresponding to 154 self-confessed designer drugs consumers in Ibiza island, were analyzed for the presence of designer drugs: amphetamine and amphetamine derivatives (methamphetamine, methylenedioxymethamphetamine (MDMA), methylenedioxyethylamphetamine (MDEA), methylenedioxyamphetamine (MDA), p-methoxymethylamphetamine (PMMA), p-methoxyamphetamine (PMA), etc.), ketamine and gamma-hydroxybutyric acid. Among this population, coming both from the forensic clinic and from the emergency room of a hospital, a total of 99 cases were found positive for some designer drug. This study shows the prevalence of methylenedioxymethamphetamine (MDMA) among designer drug users, sole or in association with other drugs. Also, the mixture of MDMA with other designer drugs, ethanol and/or cocaine is shown to be more likely to produce toxic symptoms requiring clinical attendance in a hospital emergency room. These findings along with the consumption history, the concentrations of drugs and metabolites in urine and serum and the toxicological significance for the interpretation of some MDMA metabolites such as 4-hydroxy-3-methoxymethamphetamine (HMMA) are discussed in this study.     

Impurity profiling of methamphetamine hydrochloride drugs seized in the Philippines

Methamphetamine hydrochloride is one of the most widely used illicit drugs in the Philippines. In this study, we describe the application of cluster analysis of trace impurities in the profiling of the seized methamphetamine drug samples. Thirty milligrams of a homogenized drug sample were dissolved in 1 mL of pH 10.5 buffer solution and extracted with ethyl acetate containing three internal standards. The trace impurities were identified using gas chromatography-mass spectrometry (GC-MS) and quantified by gas chromatography with a flame ionization detector (GC-FID). Following previously reported methodologies, 30 impurity peaks were selected from the GC-FID chromatograms. The peak areas and retention times were referenced to the internal standards. The peak areas of the selected peaks were then grouped for cluster analysis. In order to check for consistency of clustering, two further cluster analyses were performed using 40 and 50 impurity peaks. Changes in clustering were observed in going from 30 to 40 impurity peaks, while analyses using 40 and 50 impurity peaks gave similar results. Thus, for the seized drug samples used in this study, cluster analysis using at least 40 impurity peaks showed better consistency of clustering as compared to analysis using 30 peaks only. Ten of the impurity peaks were identified, of which four were identified for the first time in methamphetamine drug samples. These are p-bromotoluene, N-benzyl amphetamine, N-ethyl amphetamine, and N-ethyl methamphetamine. The presence of phenyl-2-propanone (P2P), N,N-dimethyl amphetamine, and N-formyl amphetamine is indicative that these casework samples were synthesized using the Leuckart method.     

Proton nuclear magnetic resonance spectroscopy (NMR) methods for determining the purity of reference drug standards and illicit forensic drug seizures

A rapid, sensitive, accurate, precise, reproducible, and versatile method for determining the purity of reference drug standards and the routine analysis of illicit drugs and adulterants using proton (1H) Nuclear Magnetic Resonance (NMR) Spectroscopy is presented. The methodology uses a weighed sample dissolved in a deuterated solvent or solvent mixture containing a high purity internal standard. The NMR experiment employs 8 scans using a 45 second delay and 90 degrees pulse. In the determination of purity of reference standards, the number of quantitative determinations available is equal to the number of peak groups that are baseline resolved. The relative standard deviation (RSD) of these signals is usually < 1% for pure standards, and the results agree well with other purity determining methods. This method can also aid in the determination of correct molecular weight for standards containing an unknown number of waters of hydration or an unknown number of acids per drug in salts. Because the molar response for the hydrogen nucleus is 1 for all compounds, and since no separation media are used, only one linearity study is required to test a probe. In the presented study, the linearity of the NMR probe was determined using methamphetamine HCl dissolved in deuterium oxide (D2O) with maleic acid as the internal standard (5 mg) for a range of concentrations from 0.033 to 69.18 mg/ml with a resulting correlation coefficient of >0.9999 for all 6 methamphetamine peak groups. The spectra of complex illicit heroin, methamphetamine, MDMA, and cocaine samples are presented, as well as an extensive list of compounds, their solubilities and the solvent(s) and internal standard used.     

Nails as useful materials for detection of methamphetamine or amphetamine abuse

Methamphetamine and amphetamine could be demonstrated in nail clippings obtained from methamphetamine users by sensitive gas chromatography/chemical ionization mass spectrometry with N-methylbenzylamine as an internal standard. The methamphetamine levels in fingernails were comparable to those in hair. Both stimulants were more concentrated in toenails than in fingernails. The detection of methamphetamine and amphetamine in nails provides an alternative informatian to that in hair on their past abuse.     

Confirmation by LC-MS of drugs in oral fluid obtained from roadside testing

The aim of this study was to assess the effectiveness of two current on-site oral fluid (OF) drug detection devices (OraLab and Dr?ger), as part of the Spanish participation in the Roadside Testing Assessment Project (ROSITA Project). The study was done in collaboration with the Spanish Traffic Police, in Galicia (NW Spain), during 2004 and 2005. A total of 468 drivers selected at the police controls agreed to participate through informed consent. In addition, saliva samples were collected and sent to the laboratory to confirm the on-site results. For this purpose, two different analytical liquid chromatography-mass spectrometry (LC-MS) methods were used to detect 11 drugs or metabolites in a 300 microL sample. Simultaneous analysis of morphine, 6-acetylmorphine, amphetamine, methamphetamine, MDA, MDMA, MDEA, MBDB, cocaine and benzoylecgonine was carried out using 100 microL of oral fluid, after an automated solid phase extraction. A different LC-MS method was performed to detect Delta(9)-THC in 200 microL of oral fluid using liquid-liquid extraction with hexane at pH 6. Both methods were fully validated, including linearity (1-250 ng/mL, 2-250 ng/mL) recovery (>50%), within-day and between-day precision (CV<15%), accuracy (mean relative error<15%), limit of detection (0.5 and 1 ng/mL), quantitation (1 and 2 ng/mL) and matrix effect. All of the positive cases and a random selection of 30% of the negatives were analyzed for confirmation analysis. Good results (sensitivity, specificity, accuracy, positive predictive value and negative predictive value>90%) were obtained for cocaine and opiates by OraLab, and for cocaine by Dr?ger. However, the results for the other compounds could be improved for both detection devices. Differences in the ease of use and in the interpretation mode (visual or instrumental) were observed.     

Simultaneous analysis of six amphetamines and analogues in hair, blood and urine by LC-ESI-MS/MS: Application to the determination of MDMA after low Ecstasy intake

A rapid and sensitive method using LC-MS/MS triple stage quadrupole for the determination of traces of amphetamine (AP), methamphetamine (MA), 3,4-methylenedioxyamphetamine (MDA), 3,4-methylenedioxymethamphetamine (MDMA, “ecstasy”), 3,4-methylenedioxyethamphetamine (MDEA), and N-methyl-1-(3,4-methylenedioxyphenyl)-2-butanamine (MBDB) in hair, blood and urine has been developed and validated. Chromatography was carried out on an Uptisphere ODB C₁₈ 5 μm, 2.1 mm × 150 mm column (Interchim, France) with a gradient of acetonitrile and formate 2 mM pH 3.0 buffer. Urine and blood were extracted with Toxitube A^® (Varian, France). Segmented scalp hair was treated by incubation 15 min at 80 °C in NaOH 1 M before liquid–liquid extraction with hexane/ethyl acetate (2/1, v/v). The limits of quantification (LOQ) in blood and urine were at 0.1 ng/mL for all analytes. In hair, LOQ was <5 pg/mg for MA, MDMA, MDEA and MBDB, at 14.7 pg/mg for AP and 15.7 pg/mg for MDA. Calibration curves were linear in the range 0.1–50 ng/mL in blood and urine; in the range 5–500 pg/mg for MA, MDMA, MDEA and MBDB, and 20–500 pg/mg for AP and MDA. Inter-day precisions were <13% for all analytes in all matrices. Accuracy was <20% in blood and urine at 1 and 50 ng/mL and <10% in hair at 20 and 250 pg/mg. This method was applied to the determination of MDMA in a forensic case of single administration of ecstasy to a 16-year-old female without her knowledge during a party. She suffered from hyperactivity, sweating and agitation. A first sample of urine was collected a few hours after (T + 12 h) and tested positive to amphetamines by immunoassay by a clinical laboratory. Blood and urine were sampled for forensic purposes at day 8 (D + 8) and scalp hair at day 60 (D + 60). No MDMA was detected in blood, but urine and hair were tested positive, respectively at 0.42 ng/mL and at 22 pg/mg in hair only in the segment corresponding to the period of the offence, while no MDA was detectable. This method allows the detection of MDMA up to 8 days in urine after single intake.     

Simultaneous screening and detection of drugs in small blood samples and bloodstains

A gas chromatography-mass spectrometry (GC-MS) method is described for the screening and detection of morphine, codeine, cocaine, benzoylecgonine, methylecgonine, cocaethylene, delta-9-tetrahydrocannabinol (THC), 11-nor-9-carboxy-THC (THC-COOH), 11-hydroxy-THC (11-OH-THC), amphetamine, methamphetamine, 3,4-methylenedioxyamphetamine (MDA), 3,4-methylenedioxymetamphetamine (MDMA) and N-methyl-1-(3,4-methylenedioxyphenyl)-2-butanamine (MBDB) in small blood samples and bloodstains using solid phase SPE columns and a pipetting robot (Gilson Aspec XL). The detection limits are in the order of 1.62-4.10 ng/50 microl spot (amphetamines), 0.15-0.82 ng/50 microl spot (cannabinoids), 1.67-4.70 ng/50 microl spot (cocaine and derivatives) and 4.53-4.91 ng/50 microl spot (opiates) and the correlation factors are between 0.9957 and 0.9999. The method has proven useful in forensic cases with only small sample volumes or bloodstains.     

The application of capillary electrophoresis for enantiomeric separation of N,N-dimethylamphetamine and its related analogs: intelligence study on N,N-dimethylamphetamine samples in crystalline and tablet forms

This paper reports a new capillary zone electrophoresis method for the simultaneous chiral determination of the enantiomers of N,N-dimethylamphetamine (DMA), methamphetamine (MA), ephedrine (E), pseudoephedrine (PE) and methylephedrine (Me-E). In this study, a number of electophoretic parameters were examined and optimized including the choice of chiral selectors, the use of short-chain tetraalkylammonium cations, the effect of chiral selector concentration, buffer concentration, applied voltage and capillary temperature. Heptakis(2,6-di-O-methyl)-beta-cyclodextrin (DM-beta-CD) and tetrabutylammonium (TBA) being the best chiral selector and buffer cation, respectively, the optimized electrophoretic conditions were found to be: 20 mM DM-beta-CD, 50 mM TBAPO(4) at pH 2.5, applied voltage at 30 kV and temperature at 25 degrees C. Under the optimized conditions, all analytes were well separated with resolution factors between 3.3 and 24.0 achieved. Using phentermine as an internal standard, the intra-day (n=8) precisions for the relative migration times and peak areas of all analytes were below 1.09%, while the inter-day precisions (n=12, 6 days) for the relative migration times and peak areas of all analytes were under 3.77%. This method has been applied to the measurement of the enantiomeric purities of the seized DMA samples. The result of the measurement could provide important clues about the possible synthetic pathways of these samples.     

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.