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Forensic Toxicology (forensic + toxicology)
Selected AbstractsMethadone and impairment in apprehended driversADDICTION, Issue 3 2009Jean-Paul Bernard ABSTRACT Aims According to Norwegian guidelines, patients who are in opioid-assisted rehabilitation programmes are permitted to drive a motor vehicle provided that certain requirements are met. The purpose of this study was to investigate apprehended drivers who had methadone in their blood at the time of apprehension and, further, the relationship between blood methadone concentration and impairment as measured by the clinical test of impairment (CTI). Methods The division of Forensic Toxicology and Drug Abuse (DFTDA) at the Norwegian Institute of Public Heath analyses blood samples from all drivers suspected of driving under the influence of drugs nation-wide. Cases with positive results for methadone in blood were collected over the period 2001,2006. Results A total of 635 drivers with methadone found in their blood samples were identified. The majority of drivers were men (>80%), aged between 30 and 40 years. Methadone was the only psychoactive drug detected in blood in only 10 cases. Benzodiazepines were a frequent finding (in approximately 90% of cases). A significant difference in blood methadone concentration was found between cases where only methadone was detected [median 0.46 mg/l (range 0.19,0.65)] and cases where methadone was detected in combination with other psychoactive drugs [median 0.28 mg/l (range 0.06,1.24)]. A CTI had been carried out, in conjunction with blood sampling, in 577 of the cases. A concentration,impairment relationship was not seen for methadone in these cases. Conclusions Cases of driving impairment involving methadone alone were very rare, with combination use most frequent. No correlation between methadone concentration and impairment as judged by the CTI was seen either for these cases or for the material as a whole. [source] Review of: Clarke's Analytical Forensic ToxicologyJOURNAL OF FORENSIC SCIENCES, Issue 1 2009Brad J. Hall Ph.D., D.A.B.F.T. No abstract is available for this article. [source] Ricin poisoning and forensic toxicology,DRUG TESTING AND ANALYSIS, Issue 4 2009Frank Musshoff Abstract Ricin is one of the most fascinating poisons due to its high toxicity: as little as 500 µg can kill an adult. It gained fame by its use in the so-called ,umbrella murder' to kill the Bulgarian dissident Georgi Markov in 1978. Ricin also became known as a potential bio-terror agent to which people could be exposed through the air, food, or water. The origin, biochemistry, toxicity, and analytical procedures for the determination of ricin are summarized. The homicide of Markov is described as well as recent cases of criminal ricin use. Copyright © 2009 John Wiley & Sons, Ltd. [source] LC-MS: a powerful tool in workplace drug testingDRUG TESTING AND ANALYSIS, Issue 3 2009E. Gallardo Abstract Workplace drug testing is a well-established application of forensic toxicology and it aims to reduce workplace accidents caused by affected workers. Several classes of abused substances may be involved, such as alcohol, amphetamines, cannabis, cocaine, opiates and also prescription drugs, such as benzodiazepines. The use of alternative biological specimens such as hair, oral fluid or sweat in workplace drug testing presents several advantages over urinalysis,mainly the fact that sample collection can be performed easily without infringing on the examinee's privacy, so the subject is more likely to perform the test. However, drugs are usually present in these alternative specimens at low concentrations and the amount of sample available for analysis is small. The use of highly sensitive techniques is therefore necessary. In fact, the successful interface of liquid chromatography with mass spectrometry (LC-MS) has brought a new light into bioanalytical and forensic sciences as it allows the detection of drugs and metabolites at concentrations that are difficult to analyse using the more commonly adopted GC-MS based techniques. This paper will discuss the importance of LC-MS in supporting workplace drug-testing programmes. The combination of LC-MS with innovative instrumentation such as triple quadrupoles, ion traps and time-of-flight mass spectrometers will also be focused. Copyright © 2009 John Wiley & Sons, Ltd. [source] Screening, library-assisted identification and validated quantification of 23 benzodiazepines, flumazenil, zaleplone, zolpidem and zopiclone in plasma by liquid chromatography/mass spectrometry with atmospheric pressure chemical ionizationJOURNAL OF MASS SPECTROMETRY (INCORP BIOLOGICAL MASS SPECTROMETRY), Issue 8 2004Carsten Kratzsch Abstract A liquid chromatographic/mass spectrometric assay with atmospheric pressure chemical ionization (LC/APCI-MS) is presented for fast and reliable screening and identification and also for precise and sensitive quantification in plasma of the 23 benzodiazepines alprazolam, bromazepam, brotizolam, camazepam, chlordiazepoxide, clobazam, clonazepam, diazepam, flunitrazepam, flurazepam, desalkylflurazepam, lorazepam, lormetazepam, medazepam, metaclazepam, midazolam, nitrazepam, nordazepam, oxazepam, prazepam, temazepam and tetrazepam, triazolam, their antagonist flumazenil and the benzodiazepine BZ1 (omega 1) receptor agonists zaleplone, zolpidem and zopiclone. It allows confirmation of the diagnosis of an overdose situation and monitoring of psychiatric patients' compliance. The analytes were isolated from plasma using liquid,liquid extraction and were separated on a Merck LiChroCART column with Superspher 60 RP Select B as the stationary phase. Gradient elution was performed using aqueous ammonium formate and acetonitrile. After screening and identification in the scan mode using the authors' LC/MS library, the analytes were quantified in the selected-ion monitoring mode. The quantification assay was fully validated. It was found to be selective proved to be linear from sub-therapeutic to over therapeutic concentrations for all analytes, except bromazepam. The corresponding reference levels the assay's accuracy and precision data for all studied substances are listed. The accuracy and precision data were within the required limits with the exception of those for bromazepam. The analytes were stable in frozen plasma for at least 1 month. The validated assay was successfully applied to several authentic plasma samples from patients treated or intoxicated with various benzodiazepines or with zaleplone, zolpidem or zopiclone. It has proven to be appropriate for the isolation, separation, screening, identification and quantification of the drugs mentioned above in plasma for clinical toxicology, e.g. in cases of poisoning, and forensic toxicology, e.g. in cases of driving under the influence of drugs. Copyright © 2004 John Wiley & Sons, Ltd. [source] A gas chromatography/mass spectrometry method for the determination of sildenafil, vardenafil and tadalafil and their metabolites in human urineRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 11 2010Sabina Strano-Rossi Sildenafil (SDF), vardenafil (VDF) and tadalafil (TDF) are phosphodiesterase type 5 enzyme inhibitors (PDE5Is), used in the treatment of erectile disorders and to improve breathing efficiency in pulmonary hypertension. The increasing incidence of their use among young athletes has drawn the attention of the anti-doping authorities to the possible abuse of PDE5Is by athletes due to their pharmacological activities. This paper describes a method for the determination in urine of PDE5Is and their metabolites by gas chromatography/mass spectrometry (GC/MS) after liquid/liquid extraction of the analytes from urine and derivatisation to obtain trimethylsilyl derivatives. The metabolic profile was studied on real samples collected from subjects taking PDE5Is (Viagra®, Levitra® or Cialis®); the main urinary metabolites were identified and their MS fragmentation characterized. The sample pre-treatment and GC/MS conditions for the detection of the metabolites have been optimised. A method for their preliminary screening and subsequent confirmation is described that takes into account the general requirements of a routine doping analysis to be used for the screening of large numbers of samples. The main metabolites identified can be included in a general purpose screening method and all the metabolites in a more specific confirmation method. The method developed has been applied for the screening of PDE5Is in 5000 urine samples. Based on the obtained results, the proposed method appears to be of practical use in analytical and forensic toxicology, including doping analysis. Copyright © 2010 John Wiley & Sons, Ltd. [source] Systematic investigation of ion suppression and enhancement effects of fourteen stable-isotope-labeled internal standards by their native analogues using atmospheric-pressure chemical ionization and electrospray ionization and the relevance for multi-analyte liquid chromatographic/mass spectrometric proceduresRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 7 2010Daniela Remane In clinical and forensic toxicology, multi-analyte procedures are very useful to quantify drugs and poisons of different classes in one run. For liquid chromatographic/tandem mass spectrometric (LC/MS/MS) multi-analyte procedures, often only a limited number of stable-isotope-labeled internal standards (SIL-ISs) are available. If an SIL-IS is used for quantification of other analytes, it must be excluded that the co-eluting native analyte influences its ionization. Therefore, the effect of ion suppression and enhancement of fourteen SIL-ISs caused by their native analogues has been studied. It could be shown that the native analyte concentration influenced the extent of ion suppression and enhancement effects leading to more suppression with increasing analyte concentration especially when electrospray ionization (ESI) was used. Using atmospheric-pressure chemical ionization (APCI), methanolic solution showed mainly enhancement effects, whereas no ion suppression and enhancement effect, with one exception, occurred when plasma extracts were used under these conditions. Such differences were not observed using ESI. With ESI, eleven SIL-ISs showed relevant suppression effects, but only one analyte showed suppression effects when APCI was used. The presented study showed that ion suppression and enhancement tests using matrix-based samples of different sources are essential for the selection of ISs, particularly if used for several analytes to avoid incorrect quantification. In conclusion, only SIL-ISs should be selected for which no suppression and enhancement effects can be observed. If not enough ISs are free of ionization interferences, a different ionization technique should be considered. Copyright © 2010 John Wiley & Sons, Ltd. [source] Application of tandem mass spectrometry combined with gas chromatography and headspace solid-phase dynamic extraction for the determination of drugs of abuse in hair samplesRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 5 2003Dirk W. Lachenmeier A new method combination, headspace solid-phase dynamic extraction coupled with gas chromatography/tandem mass spectrometry (HS-SPDE/GC/MS/MS), is introduced to determine drugs of abuse in hair samples. This highly automated procedure utilizes SPDE for pre-concentration and on-coating derivatization as well as GC and triple quadrupole MS/MS for selective and sensitive detection. All these steps, apart from washing and cutting of the hair samples, are performed without manual intervention on a robot-like autosampler. SPDE is a solventless extraction technique related to solid-phase microextraction (SPME). The analytes are absorbed from the sample headspace directly into a hollow needle with an internal coating of polydimethylsiloxane by repeated aspirate/dispense cycles. The HS-SPDE/GC/MS/MS procedure was applied to the analysis of methadone, the trimethylsilyl derivatives of cannabinoids and the trifluoroacetyl derivatives of amphetamines and designer drugs. The method was shown to be sensitive with detection limits between 6 and 52 pg/mg hair matrix and precision between 0.4 and 7.8% by the use of an internal standard technique. Linearity was obtained from 0.1,20,ng/mg with coefficients of correlation between 0.995 and 0.999. Compared with conventional methods of hair analysis, HS-SPDE/GC/MS/MS is easier to use, substantially faster, with the degree of sensitivity and reproducibility demanded in clinical and forensic toxicology. The main advantage of the SPDE technique in relation to SPME is the robustness of the capillary. Copyright © 2003 John Wiley & Sons, Ltd. [source] Characterization and determination of chlorophacinone in plasma by ion chromatography coupled with ion trap electrospray ionization mass spectrometryBIOMEDICAL CHROMATOGRAPHY, Issue 5 2009Xiao-kun OuYang Abstract Plasmatic chlorophacinone is commonly measured with liquid chromatographic assay, which convenient but lacks sensitivity and selectivity and usually requires ion pair reagents to reduce the chromatographic tailed peak. In this paper, a novel method using eluent generator reagent-free ion chromatography coupled with electrospray ionization ion trap mass spectrometric detection for the determination of chlorophacinone in plasma has been developed. After samples were extracted with 10% (v/v) methanol in acetonitrile and cleaned by solid-phase extraction, chromatographic separation was performed on an IonPac® AS11 analytical column (250 × 4.0 mm) using 40.0 mmol/L KOH containing 10% (v/v) methanol as organic modifier. Quantification was performed by negative electrospray ionization in multiple reaction monitoring mode. The transition m/z 373 , 201 was for the quantification ion; the transitions m/z 373 , 172 and m/z 373 , 145, as well as the isotope ions m/z 375 and m/z 203, were for the qualitative ions. All the method parameters were validated. It was confirmed that this method can be used in clinical diagnosis and forensic toxicology. Copyright © 2008 John Wiley & Sons, Ltd. [source] | ||||||||||