Development of a capillary zone electrophoresis method including a factorial design and simplex optimisation for analysis of amphetamine, amphetamine analogues, cocaine, and heroin

A capillary zone electrophoresis (CZE) method was developed for the analysis of amphetamine and 13 amphetamine analogues. A full factorial design was used to screen for important design variables (i.e. carrier electrolyte concentration, pH, and separation temperature), and a modified simplex was employed in a final optimisation step. The resolution values of the target compounds were used as responses in the screening and optimisation phases. This approach made it possible to control the effects of the design variables on the separation of the target compounds. The best results were obtained using a 100mM Tris/phosphate buffer (pH 3.1) at a separation temperature of 10 degrees C, and the analysis time was 23 min under these conditions. After slight modification, the method also enabled baseline resolution of the most commonly encountered amphetamine derivatives, as well as cocaine and heroin, within 7 min. There was a linear relationship between peak area and concentration for all substances, with correlation coefficients in the range of 0.9975-0.9999. Moreover, the technique was repeatable and exhibited relative standard deviation (R.S.D.) values in the ranges of 0.01-0.11% and 0.54-1.60% for relative migration time and corrected peak area, respectively. Lastly, the method was successfully applied to analyse street samples.     

Raman Spectroscopy as a Simple,Rapid, Nondestructive Screening Test for Methamphetamine in Clandestine Laboratory Liquids

Raman spectroscopy has found increased use in the forensic controlled substances laboratory in recent years due to its rapid and nondestructive analysis capabilities. Here, Raman spectroscopy as a screening test for methamphetamine in clandestine laboratory liquid samples is discussed as a way to improve the efficiency of a laboratory by identifying the most probative samples for further workup among multiple samples submitted for analysis. Solutions of methamphetamine in ethanol, diethyl ether, and Coleman fuel were prepared in concentrations ranging from 0.5% to 10% w/v, and Raman spectra of each were collected. A concentration‐dependant Raman peak was observed at 1003 per cm in each solution in 4% w/v and greater solutions. Case samples were analyzed and also found to reliably contain this diagnostic peak when methamphetamine was present. The use of this diagnostic indicator can save the forensic controlled substances laboratory time and materials when analyzing clandestine laboratory liquid submissions.     

Screening experiments of ecstasy street samples using near infrared spectroscopy

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.     

Use of dynamically coated capillaries for the routine analysis of methamphetamine, amphetamine, MDA, MDMA, MDEA, and cocaine using capillary electrophoresis

A rapid, accurate, precise, reproducible, economical, and environmentally gentle method using capillary electrophoresis (CE) is presented for the routine analysis of methamphetamine, amphetamine, MDA, MDMA, MDEA, and cocaine in seized drugs. The methodology uses a 32 cm by 50 microm capillary (length to detector 23.5 cm) with a commercially available buffer kit and diode array UV detection. Dynamic coating of the capillary surface is accomplished by flushing with base for 1 min, a proprietary polycation for 1 min, and then a proprietary polyanion for 2 min. This approach provides a relatively high and stable electroosmotic flow (EOF), even at low pHs. The background electrolyte (BGE) contains 75 mM phosphate buffer (pH 2.5) with the same polyanion as above. Using this methodology, amphetamine, methamphetamine, MDA, MDMA, MDEA, and an internal standard (n-butylamphetamine) are baseline resolved in less than 5 min. The run-to-run migration time %RSDs and peak area %RSDs are typically <0.3% and <2.1%, respectively. The day-to-day and capillary-to-capillary migration time %RSDs are <1.5% and <2.1%, respectively. The %RSDs of the relative migration times compared with the internal standard on a day-to-day and capillary-to-capillary basis are <0.2% and <0.06%, respectively. The linear dynamic range using peak areas range from 0.003 to 0.10 mg/mL. The correlation coefficients are >0.9998, with all calibration curves passing at or near the origin. Similar data are obtained for cocaine and its internal standard henyltoloxamine. None of the compounds usually encountered in illicit samples interfere with the target compound (e.g., methamphetamine and cocaine) or the internal standard. Quantitative results for synthetic mixtures and seized exhibits are in good agreement with actual values, and also with results obtained from other techniques. The relatively high EOF for the dynamically coated capillary system allows for the screening of basic, acidic, and neutral adulterants in drug seizures; identification is facilitated by the use of automated UV library searches.     

Fourier transform infrared/Raman differentiation and characterization of cis- and trans-2,5-dimethoxy-4,beta-dimethyl-beta-nitrostyrenes: precursors to the street drug STP.

Fourier transform Raman and infrared spectra of pure cis(Z)- and trans(E)-2,5-dimethoxy-4,beta-dimethyl-beta-nitrostyrene (precursors of the psychotomimetic street drug STP or DOM) were recorded in the solid state. The spectra show characteristic features of the ethylene moiety and of the aryl and nitro substituents which permit ready differentiation and identification of these isomers. A very strong Raman line at 1670 cm-1 from the cis isomer for the C=C stretching mode, in comparison with a strong Raman line at 1641 cm-1 for the trans isomer, affords primary differentiation of these substances. A second characteristic, of both the Raman and infrared (IR) spectra, is that the frequency of the strong symmetric nitro (NO2) stretching band is about 40 cm-1 higher in the cis (1346 cm-1) than the trans isomer (1301 cm-1). All major IR and Raman bands are reported and given vibrational assignments.     

大鼠死后脑组织的傅里叶变换红外光谱变化

目的应用傅里叶变换红外（Fourier transform infrared．FTIR）光谱技术分析大鼠死后脑组织随死亡时间推移的化学变化过程,为死亡时间推断的研究提供新的途径与数据。方法大鼠断颈处死后置于（30±2）℃环境下,在不同时间点提取大鼠脑皮质．运用FTIR光谱仪检测不同化学基团的变化。结果随着死亡时间的推移,大鼠脑组织FTIR光谱的主要吸收峰峰位没有明显变化．而其峰强有明显差异：（1）与核酸有关的谱带的相对峰强呈明显下降趋势;（2）酰胺Ⅰ、Ⅱ的峰强比（I1647/I1541）呈下降趋势;（3）1456和1398cm^-1谱带的峰强各自呈下降和上升趋势;（4）2852、2871、2923和2958cm^-1谱带的峰强相对于1647cm^-1而言．呈上升趋势。结论脑组织可以作为FTIR光谱技术分析死亡时间的适用检材。     

Characterization of the explosive triacetone triperoxide and detection by ion mobility spectrometry

The improvised explosive triacetone triperoxide (TATP) was synthesized and characterized by 1H-nuclear magnetic resonance (NMR), 13C-NMR, Raman and infrared (IR) spectroscopy. Triacetone triperoxide was subsequently analyzed by ion mobility spectrometry (IMS) in positive ion mode, and detected as a cluster of three peaks with a drift time of the most intense peak at 13.06 ms. Triacetone triperoxide was then analyzed after dissolution in toluene, where a dramatic increase in peak intensity was observed, at a flight time of 12.56 ms (K0=2.71 cm2V(-1)s(-1)). Triacetone triperoxide was subsequently analyzed by coupling the ion mobility spectrometer to a triple quadrupole mass spectrometer, where a single peak at m/z of 223 atomic mass units identified the species present in the ion mobility spectra as being triacetone triperoxide.     

Identification of Different Forms of Cocaine and Substances Used in Adulteration Using Near‐infrared Raman Spectroscopy and Infrared Absorption Spectroscopy

Identification of cocaine and subsequent quantification immediately after seizure are problems for the police in developing countries such as Brazil. This work proposes a comparison between the Raman and FT‐IR techniques as methods to identify cocaine, the adulterants used to increase volume, and possible degradation products in samples seized by the police. Near‐infrared Raman spectra (785 nm excitation, 10 sec exposure time) and FT‐IR‐ATR spectra were obtained from different samples of street cocaine and some substances commonly used as adulterants. Freebase powder, hydrochloride powder, and crack rock can be distinguished by both Raman and FT‐IR spectroscopies, revealing differences in their chemical structure. Most of the samples showed characteristic peaks of degradation products such as benzoylecgonine and benzoic acid, and some presented evidence of adulteration with aluminum sulfate and sodium carbonate. Raman spectroscopy is better than FT‐IR for identifying benzoic acid and inorganic adulterants in cocaine.     

拉曼光谱快速定性分析合成毒品

目的快速定性检测合成毒品;方法利用激光拉曼光谱仪对合成毒品进行检验;结果合成毒品苯丙胺、甲基苯丙胺、氯胺酮、麻黄碱、甲基麻黄碱均能被拉曼准确检出;结论激光拉曼光谱能对合成毒品快速定性分析。     

The application of chemometrics on Infrared and Raman spectra as a tool for the forensic analysis of paints

The aim of this work is to evaluate the capabilities and limitations of chemometric methods and other mathematical treatments applied on spectroscopic data and more specifically on paint samples. The uniqueness of the spectroscopic data comes from the fact that they are multivariate - a few thousands variables - and highly correlated. Statistical methods are used to study and discriminate samples. A collection of 34 red paint samples was measured by Infrared and Raman spectroscopy. Data pretreatment and variable selection demonstrated that the use of Standard Normal Variate (SNV), together with removal of the noisy variables by a selection of the wavelengths from 650 to 1830 cm(-1) and 2730-3600 cm(-1), provided the optimal results for infrared analysis. Principal component analysis (PCA) and hierarchical clusters analysis (HCA) were then used as exploratory techniques to provide evidence of structure in the data, cluster, or detect outliers. With the FTIR spectra, the Principal Components (PCs) correspond to binder types and the presence/absence of calcium carbonate. 83% of the total variance is explained by the four first PCs. As for the Raman spectra, we observe six different clusters corresponding to the different pigment compositions when plotting the first two PCs, which account for 37% and 20% respectively of the total variance. In conclusion, the use of chemometrics for the forensic analysis of paints provides a valuable tool for objective decision-making, a reduction of the possible classification errors, and a better efficiency, having robust results with time saving data treatments.     

Passport examination by polarized infrared spectra

In this study, a new nondestructive technique for passport examination is proposed. In this technique, linearly polarized light is used to measure Fourier transform infrared (FT-IR) reflectance spectra of films on the biographical data page. Thirty genuine and thirty-five counterfeit Japanese passports and five marketed films pasted on name cards were examined. The measured spectra were analyzed as follows. The absorption spectra were obtained by the Kramers-Kronig transformations of reflectance spectra. The peak ratios were then calculated from the absorption spectra by adding the peak areas at 1126 and 1263 cm(-1) and dividing the result by the peak area at 1727 cm(-1). When nonpolarized light was used, the samples could not be distinguished by comparing the peak ratios. However, when polarized light was used, they were successfully distinguished by the comparison. Therefore, polarized light is useful for the forensic discrimination of passport films by the measurement of FT-IR spectra.     

激光拉曼光谱对苯骈杂氮（堇）类药物的定性检测

目的 建立用拉曼光谱检测苯骈杂氮革类药物的定性方法.方法 利用激光拉曼光谱仪对10种苯骈杂氮革类药物进行检验.结果 10种苯骈杂氮（萆）类药物的主成分均能被拉曼准确检出.结论 该法能较好地对苯骈杂氮革类药物固体样品快速定性分析.     

NIR analysis of cellulose and lactose--application to ecstasy tablet analysis

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.     

红外光谱法用于安钠咖中咖啡因和苯甲酸钠快速定性和定量分析

目的建立安钠咖样品中咖啡因和苯甲酸钠快速定性和定量分析的红外光谱方法。方法采用高纯度咖啡因和苯甲酸钠混合制样的方法制备定性和定量建模样品,通过分析混合样品的红外光谱图,确定安钠咖样品中咖啡因和苯甲酸钠的特征吸收峰。采用偏最小二乘法(partial least squares,PLS)建立红外光谱定量模型。结果通过分析17个咖啡因和苯甲酸钠混合样品(咖啡因纯度范围10%~80%)的红外光谱图,确定了咖啡因的特征吸收峰为1698、1650、1237、972、743、609cm-1;苯甲酸钠的特征吸收峰为1596、1548、1406、845、708、679cm-1。将所有特征吸收峰均检出作为阳性判断依据时,48个安钠咖缴获样品中咖啡因和苯甲酸钠的阳性检出率均为100%。咖啡因PLS定量模型的线性范围为10%~80%,决定系数(R2)为99.9%,交叉验证均方差(root mean square error of cross validation,RMSECV)为0.68%,预测均方差(root mean square error of prediction,RMSEP)为0.91%;苯甲酸钠PLS定量模型的线性范围为20%~90%,R2为99.9%,RMSECV为0.91%,RMSEP为1.11%。配对样本t检验结果显示,高效液相色谱法和红外光谱法的测定结果差异无统计学意义。采用所建立的红外定量方法分析48个安钠咖缴获样品,咖啡因的纯度为27.6%~63.1%,苯甲酸钠的纯度为36.9%~72.3%。结论采用红外光谱法对安钠咖样品中的咖啡因和苯甲酸钠进行快速定性和定量分析,可提高检验鉴定效率、降低检验成本。     

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.     

莫达非尼药片的激光共聚焦显微拉曼光谱快速检验

目的建立莫达非尼药片的拉曼光谱快速定性检验方法。方法莫达非尼对照品和药片检材分别研磨后经拉曼光谱检验得到拉曼谱图。结果经比较,二者图谱一致,确定检出莫达非尼成分,结果可靠。结论莫达非尼药片在本文所述的条件下有较好的响应,峰型较好,峰位准确,同时药片中的淀粉等物质干扰较小。本文所建立的拉曼光谱检验方法,简便、高效、准确,可供一线执法、检验部门对查获的莫达非尼药片进行快速的定性检验。     

The use of supercritical fluid extraction for the determination of amphetamines in hair

A laboratory study interested in the analysis of human hair for drugs-of-abuse was conducted to determine if drugs could be detected and quantified from hair. Supercritical fluid extraction (SFE) techniques followed by GC-MS analysis were applied to extract amphetamines from hair. The group of amphetamines included methylenedioxyamphetamine (MDA), methylenedioxymetamphetamine (MDMA), methylenedioxyethylamphetamine (MDEA) and internal standard mephentermine (MP). To validate information on amphetamine use in hair, powdered hair samples free from drugs were collected and soaked in a known amphetamine standard solution. Authentic fortified case hair samples taken from known drug users known to have consumed amphetamines were also analyzed for amphetamine. Results from this study show that amphetamine use can be detected in spiked and authentic fortified human hair using SFE techniques for qualitative and quantitative reproducible results.     

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.     

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.     

A market study of green spray paints by Fourier transform infrared (FTIR) and Raman spectroscopy.

A market study of 40 different green spray paints was carried out using infrared (FTIR) and Raman spectroscopy. The infrared technique distinguished between the 12 main groups based on their binder and extender composition. After visual comparison of the spectra 22 subgroups were observed. Raman spectroscopy was also carried out on the 40 reference paints in order to determine the pigment content. Analyses were undertaken using two different excitation sources: Argon ion (514.5 nm) and Helium-Neon (632.8 nm). The first generated strong fluorescence for most of the samples and created eight groups. Using the red laser, 15 classes were observed. Finally, using an analytical sequence starting with infrared spectroscopy followed by Raman Helium-Neon and then by Raman Argon laser, most of the paints were differentiated. In this study infrared and Raman spectroscopy complemented each other. FTIR supplied information about the binder and some extenders, and Raman provided information on the main organic pigments present.