A preliminary study of the analysis of explosives using packed-column supercritical fluid chromatography with atmospheric pressure chemical ionisation mass spectrometric detection

A packed-column supercritical fluid chromatographic (SFC) separation of explosive compounds hyphenated to atmospheric pressure chemical ionisation (APCI) mass spectrometric (MS) detection has been developed. Nitroaromatics, nitramines and nitrate esters can be resolved and identified, with theoretical limits of detection of approximately 100 ng on column. This represents a development over previously described gas chromatography–thermal energy analysis (GC–TEA), gas chromatography– electron capture detection (GC–ECD) and SFC methods for the analysis of explosives due to the molecular identification afforded by the mass spectrometry. Explosives in the combinations expected in commercially available mixtures can be separated and identified. A successful application to a laboratory trial simulating casework is described.     

Rapid analysis of caffeine in "smart drugs" and "energy drinks" by microemulsion electrokinetic chromatography (MEEKC)

A novel method based on microemulsion electrokinetic chromatography (MEEKC) with diode array detection (DAD) for rapid determination of caffeine in commercial and clandestine stimulants, known as "energy drinks" and "smart drugs", is described. Separations were carried out in 50 cm × 50 μm (ID) uncoated fused silica capillaries. The optimized buffer electrolyte was composed of 8.85 mM sodium tetraborate pH 9.5, SDS 3.3% (w/v), n-hexane 1.5% (v/v) and 1-butanol 6.6% (v/v). Separations were performed at a voltage of 20 kV. Sample injection conditions were 0.5 psi, 3 s. Diprofilline was used as internal standard. The determination of the analytes was based on the UV signal recorded at 275 nm, corresponding to the maximum wavelength of absorbance of caffeine, whereas peak identification and purity check was performed on the basis of the acquisition of UV radiation between 200 and 400 nm wavelengths. Under the described conditions, the separation of the compounds was achieved in 6 min without any interference from the matrix. Linearity was assessed within a caffeine concentration range from 5 to 100 μg/mL. The intra-day and inter-day precision values were below 0.37% for migration times and below 9.86% for peak areas. The present MEEKC method was successfully applied to the direct determination of caffeine in smart drugs and energy drinks.     

A method for the rapid detection of the zopiclone degradation product 2-amino-5-chloropyridine

Zopiclone (Zimovane) is a cyclopyrrolone compound which exhibits hypnotic and sedative effects while also exhibiting anticonvulsant and muscle relaxant activities. The detection and quantification of zopiclone is difficult. It has a high molecular weight compared to most other commonly used drugs, therapeutic levels are not high, and it is unstable in nucleophilic solvents. A degradation product of zopiclone, 2-amino-5-chloropyridine (ACP) together with a method for its detection using high-performance liquid chromatography with diode array detection has been described previously. An account is presented of a simple method for the detection of ACP using gas chromatography with mass selective detection (GC/MS) which will facilitate detection of zopiclone use as part of a routine screen.     

Supercritical fluid chromatography in forensic science: a critical appraisal

The application of supercritical fluid chromatography (SFC) in forensic science is reviewed. The applications centre on the analysis of explosives and of drugs of abuse. The systems employed are discussed in the context of comparison with gas chromatography and high-performance liquid chromatography methods which are traditionally used for such analyses. The advantages and disadvantages of SFC over these methods are discussed. Recommendations are made for the developments which are required in SFC technology if it is to find greater application in forensic science.     

Analysis of etorphine in postmortem samples by HPLC with UV diode-array detection

Etorphine is a synthetic narcotic analgesic usually used in veterinary medicine. It possesses an analgesic potency up to 1000 times greater than morphine and is therefore used in low doses, primarily for tranquilising large animals. For veterinary use, etorphine is usually available in its commercial formulation as Immobilon^®, when in combination with acepromazine or methotrimeprazine. Due to the potency of etorphine, only very low doses are required to produce adverse or fatal effects. This paper describes a method for detecting and quantifying etorphine using HPLC with UV diode array detection (HPLC–DAD) and demonstrates the advantage of the technique for the detection of Immobilon^® at low doses. In a forensic case involving Immobilon^®, the etorphine concentrations measured in postmortem femoral vein and heart blood specimens were 14.5 and 23.5 μg/l, respectively. No etorphine was detected in the urine. To our knowledge this is the first time postmortem etorphine concentrations have been reported.     

Forensic intoxication with clobazam: HPLC/DAD/MSD analysis

Clobazam (Castillium, Urbanil), a benzodiazepine often used as an anxiolytic and in the treatment of epilepsy, is considered a relatively safe drug. The authors present a fatal case with a 49-year-old female, found dead at home. She had been undergoing psychiatric treatment and was a chronic alcoholic. The autopsy findings were unremarkable, except for multivisceral congestion, steatosis and a small piece of a plastic blister pack in the stomach. Bronchopneumonia, bronchitis and bronchiolitis were also diagnosed. Anhigh-performance liquid chromatography (HPLC)/diode array detector (DAD)/mass spectrometry detection (MSD) with electrospray method was developed in order to detect, confirm and quantify clobazam in the post-mortem samples. In the chromatographic separation, a reversed-phase column C18 (2.1 x 150 mm, 3.5 microm) was used with a mobile phase of methanol and water, at a 0.25 ml/min flow rate. Carbonate buffer (pH 10.5) and 20 microl of prazepam (100 microg/ml) as internal standard were added to the samples. A simple and reliable liquid-liquid extraction method for the determination of clobazam in post-mortem samples was described. Calibration curves for clobazam were performed in blood, achieving linearity between 0.01 and 10 microg/ml and a detection limit of 1.0 ng/ml. The clobazam concentration found in post-mortem blood was 3.9 microg/ml, higher than the reported therapeutic concentration (0.1-0.4 microg/ml). The simultaneous acquisition by photodiode array detection and mass spectrometry detection results allowed benzodiazepines to be identified with sufficient certainty. An examination of all the available information suggested that death resulted from respiratory depression due to clobazam toxicity.     

The application of chromatography and spectrometry for the analysis of ketorolac and diclofenac in biological fluids

The objective of the present work was to study conditions for isolation of ketorolac and diclofenac from biological fluids. A method of their extraction with a mixture of organic solvents has been developed and the conditions for the identification of these compounds are proposed with the use of high performance liquid chromatography (HPLC), UV spectroscopy, and gas chromatography with electron capture detection (GC/ECD). The possibilities of using HPLC, UV spectrometry, and GC/ECD for quantitative determination of ketorolac and diclofenac are illustrated.     

HPLC-DAD determination of mepivacaine in cerebrospinal fluid from a fatal case

A fatal case involving mepivacaine-induced epidural anesthesia is described. The pathological findings were typical of cardiac shock from ischemic origin. Cerebrospinal fluid (CSF) was obtained several hours after death and mepivacaine was identified by gas chromatography-mass spectrometry (GC-MS). Its concentration was determined by high performance liquid chromatography with diode array detection (HPLC-DAD). Extraction from CSF was performed by deproteinization with acetonitrile. The mepivacaine concentration in the sample was 264 microg/mL. Concentrations of mepivacaine in CSF following epidural anesthesia are not reported in literature to our knowledge. This is the first reported case of death in which the mepivacaine concentration in CSF has been determined.     

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.     

Rapid enantiomeric analysis of zopiclone in serum by supercritical fluid chromatography–tandem mass spectrometry

Zopiclone (ZOP) is a hypnotic drug prescribed to treat insomnia. Due to the chiral nature of ZOP, the psychologically active S-form and inactive R-form need to be determined enantiomerically in a forensic drug analysis. In the present study, a supercritical fluid chromatography (SFC) method was designed with a faster analysis ability than that of previously reported techniques. The SFC–tandem mass spectrometry (SFC–MS/MS) method was optimized using a column with a chiral polysaccharide stationary phase (Trefoil CEL2). ZOP was extracted from pooled human serum using solid-phase extraction (Oasis HLB) and analyzed. The developed SFC–MS/MS method achieved the baseline separation of S-ZOP and R-ZOP within 2 min. The fit-for-purpose method validation indicated that the optimized solid-phase extraction achieved near complete recovery and approximately 70% of the matrix effect. Both the retention time and peak area showed sufficient precision. The lower and upper limits of quantification (LOQ) were 5.7 × 10⁻² ng/mL and 25 ng/mL for R-ZOP, and 5.2 × 10⁻² ng/mL and 25 ng/mL for S-ZOP. The calibration line was linear in the range from lower LOQ to upper LOQ. The stability test indicated that ZOP in serum stored in a refrigerator (4°C) degraded and about 55% remained in 31 days. The quick analysis of the SFC–MS/MS method makes it a valid option for the enantiomeric analysis of ZOP.     

Liquid chromatography/photodiode array detection for determination of strychnine in blood: a fatal case report

An original liquid chromatography method with photodiode-array detection (DAD) is presented for the determination of strychnine in blood. This sensitive method allows the use of only 0.1 ml of sample. The strychnine was isolated from blood using a liquid-liquid extraction procedure and chloroquine as an internal standard. The limits of detection (LOD) and quantification were 0.06 and 0.5 mg/l, respectively. The recovery was 94% and the coefficients of variation (CV) ranged from 5.9 to 10.8%. A fatal case of strychnine poisoning is presented, with a lethal blood concentration of 25 mg/l.     

Enantiomeric separation of methamphetamine and related analogs by capillary zone electrophoresis: intelligence study in routine methamphetamine seizures

A method for simultaneous enantiomeric separation of ephedrine, pseudoephedrine, and methamphetamine (MA) in a single run by simple capillary zone electrophoresis (CZE) with beta-cyclodextrin as a chiral selector is described. The effects of the buffer pH, phosphate concentration, beta-cyclodextrin concentration, voltage and temperature on the peak resolution were examined. Good enantiomeric resolution was attained for each analyte under our optimized conditions: 15 mM beta-cyclodextrin, 300 mM NaH2PO4 at pH 2.5 with an uncoated capillary (64.5 cm x 50 microm), applied potential at 20 kV and temperature at 30 degrees C. Ultraviolet (UV) detection at a fixed wavelength (200 nm) was employed using a diode array detector. Using phentermine as an internal standard, migration times for all analytes are reproducible within 0.16% for intra-day and 0.6% for inter-day runs. Application of this method to the analysis of confiscated drugs is discussed.     

Gas chromatography/tandem mass-spectrometry assay for trace amounts of 3'-hydroxystanozolol

3'-Hydroxystanosolol detection in biological fluids at pg levels by gas chromatography/tandem mass spectrometry is described. Gas chromatography/high resolution mass spectrometry results can be confirmed with gas chromatography/tandem mass-spectrometry.     

Comparison of the prevalence of alcohol,cannabis and other drugs between 900 injured drivers and 900 control subjects: results of a French collaborative study

A collaborative case-control study was conducted in France in order to determine the prevalence of alcohol, cannabinoids, opiates, cocaine metabolites, amphetamines and therapeutic psychoactive drugs in blood samples from drivers injured in road accidents and to compare these values with those of a control population. Recruitment was performed in emergency departments of six university or general hospitals and comprised 900 drivers involved in a non-fatal accident and 900 patients (controls) who attended the same emergency units for a non-traumatic reason. Drivers and controls were matched by sex and age. Alcohol was determined by flame ionization-gas chromatography, drugs of abuse (DOA) by gas chromatography-mass spectrometry with the same analytical procedures in the six laboratories, and medicines by high performance liquid chromatography with diode array detection. Blood alcohol concentration exceeding 0.5 g/l (i.e. the legal French threshold) was found in 26% of drivers and 9% of controls. In the 18-27 years age range, alcohol was the only toxic found in blood samples of 17% drivers and 5% controls, leading to an odds-ratio (OR) of 3.8. A significant relationship was found between alcohol blood concentrations and OR values. All age groups confounded, the main active substance of cannabis, Delta(9) tetrahydrocannabinol (THC), was found in 10% of drivers and 5% of controls. In the less than 27 years old, THC (>1 ng/ml) was detected alone in the blood of 15.3% drivers and of 6.7% controls, giving OR=2.5, whereas there was no link between THC blood concentrations and OR value. THC was found alone in 60% of cases and associated with alcohol in 32%, with OR=4.6 between drivers and controls for this association. The difference in morphine prevalence between drivers (2.7%) and controls (0.03%) was highly significant (P<0.001), with OR=8.2. The number of positive cases for amphetamines and cocaine metabolites was too low for reaching any interpretation. The most frequently observed psychoactive therapeutic drugs were by far benzodiazepines, that were found alone in 9.4% of drivers and 5.8% of controls, which led to OR=1.7 (P<0.01).This study demonstrates a higher prevalence of opiates, alcohol, cannabinoids and the combination of these last two compounds in blood samples from drivers involved in road accidents than in those from controls, which suggests a causal role for these compounds in road crashes.     

Hair analysis for drug abuse: I. Determination of methamphetamine and amphetamine in hair by stable isotope dilution gas chromatography/mass spectrometry method

Determination of methamphetamine and amphetamine in hair was performed by gas chromatography/mass spectrometry using stable isotope-labeled internal standards, 2-methylamino-1-phenylpropane-2,3,3,3-d4 and 2-amino-1-phenylpropane-2,3,3,3-d4. Extraction of hair with methanol/5M hydrochloric acid (20:1) using ultrasonication was chosen as the standard method. The calibration curves for amphetamines in the hair were linear from 1 to 100 ng/mg (r greater than 0.99). The detection limit was 0.5 ng/mg at the 95% confidence level. The coefficients of variation (CV) (n = 8) of analysis using the spiked hair with methamphetamine were from 0.7 to 6%. The CV (n = 8) of analysis of the methamphetamine abuser's hair was 17.5%. Sectional analysis of monkey and human hair after methamphetamine ingestion suggested a good correlation between the duration of drug use and drug distribution in the hair.     

Simultaneous Quantitative Determination of Amphetamines,Opiates, Ketamine,Cocaine and Metabolites in Human Hair: Application to Forensic Cases of Drug Abuse

A method using liquid chromatography–tandem mass spectrometry (LC–MS/MS) to simultaneously quantify amphetamines, opiates, ketamine, cocaine, and metabolites in human hair is described. Hair samples (50 mg) were extracted with methanol utilizing cryogenic grinding. Calibration curves for all the analytes were established in the concentration range 0.05–10 ng/mg. The recoveries were above 72%, except for AMP at the limit of quantification (LOQ), which was 48%. The accuracies were within ±20% at the LOQ (0.05 ng/mg) and between −11% and 13.3% at 0.3 and 9.5 ng/mg, respectively. The intraday and interday precisions were within 19.6% and 19.8%, respectively. A proficiency test was applied to the validated method with z-scores within ±2, demonstrating the accuracy of the method for the determination of drugs of abuse in the hair of individuals suspected of abusing drugs. The hair concentration ranges, means, and medians are summarized for abused drugs in 158 authentic cases.     

A fatal forensic intoxication with fenarimol: analysis by HPLC/DAD/MSD

Fenarimol (Rubigan) is a pyrimidine ergosterol biosynthesis inhibitor used as a systemic fungicide. The authors present a fatal fenarimol intoxication case analysed in the Forensic Toxicology Service of the National Institute of Legal Medicine. The results were used to compare two different HPLC techniques, regarding selectivity and sensitivity: an HPLC system with a diode array detector (DAD) and an HPLC system with a DAD and a mass spectrometry detector (MSD) with an electrospray interface. All biological samples were submitted to a solid-phase extraction procedure. The detection and quantification limits of fenarimol, linearity, precision and accuracy were evaluated. The fenarimol concentration levels determined were of 89.0 mg/ml in gastric contents, 1.9 mg/g in liver and 0.4 mg/g in kidney. Blood was not available at autopsy. No published data related to fenarimol self-poisoning were found, so it was not possible to interpret the results obtained by comparison with toxic/lethal levels.     

Fast gas chromatography of explosive compounds using a pulsed-discharge electron capture detector

The detection of a mixture of nine explosive compounds, including nitrate esters, nitroaromatics, and a nitramine in less than 140 sec is described. The new method employs a commercially available pulsed-discharge electron capture detector (PDECD) coupled with a microbore capillary gas chromatography (GC) column in a standard GC oven to achieve on-column detection limits between 5 and 72 fg for the nine explosives studied. The PDECD has the benefit that it uses a pulsed plasma to generate the standing electron current instead of a radioactive source. The fast separation time limits on-column degradation of the thermally labile compounds and decreases the peak widths, which results in larger peak intensities and a concomitant improvement in detection limits. The combination of short analysis time and low detection limits make this method a potential candidate for screening large numbers of samples that have been prepared using techniques such as liquid-liquid extraction or solid-phase microextraction.     

The rapid analysis of heroin drug seizures using micellar electrokinetic chromatography with short-end injection

A simple and rapid method for the analysis of heroin seizures by micellar electrokinetic chromatography with short-end injection is described. Separations were performed using an uncoated fused silica capillary, 50 cm x 50 microm I.D. x 360 microm O.D. with an effective separation length of 8 cm. The system was run at 25 degrees C with an applied negative voltage of -25 kilovolts. Injection of each sample was for 2 s at -50 mbar. UV detection was employed with the wavelength set at 210 nm. The background electrolyte consisted of 85:15 (water:acetonitrile, v/v) containing final concentrations of 25 mM SDS and 15 mM sodium borate, pH 9.5. Samples and standards were prepared in 0.1% v/v acetic acid and diluted in the run buffer containing 1 mg/ml of N,N-dimethyl-5-methoxytryptamine as an internal standard. Under these conditions a text mixture containing caffeine, paracetamol, morphine, codeine, heroin, and acetylcodeine was resolved within 1.5 min. The method was used to determine the concentration of heroin in heroin seizure samples, and the results were in good agreement with those obtained by a validated gas chromatographic method.     

SPME-GC\NPD法快速分析尿液中苯丙胺类化合物

建立了ＳＰＭＥ－ＧＣ／ＮＰＤ法同时分析尿液中九种苯丙胺类化合物的方法。取１ｍｌ尿样以４－苯基丁胺为内标,在碱性条件下,将１００μｍＰＤＭＳ纤维头浸入尿液中２０ｍｉｎ,气相色谱进样后热解吸３ｍｉｎ,用ＧＣ／ＮＰＤ进行测定。九种苯丙胺类化合物及内标完全分离,五种苯丙胺类化合物分别在０．０５～１５、０．１～１５、０．２～１５μｇ／ｍｌ浓度范围内线性良好,ｒ为０．９９２８～０．９９９５,变异系数均小于１０％。方法简便、快速、准确,可用于尿液中苯丙胺类违禁药物的检测