Sys Stybe Johansen

Simultaneous screening and quantification of 52 common pharmaceuticals and drugs of abuse in hair using UPLC–TOF-MS

An UPLC-TOF-MS method for simultaneous screening and quantification of 52 drugs in hair was developed and validated. The selected drugs represent the most common classes of pharmaceuticals and drugs of abuse such as amphetamines, analgesics, antidepressants, antipsychotics, benzodiazepines, cocaine, ketamine and opioids. Hair samples were extracted with methanol:acetonitrile:ammonium formate (2 mM, 8% acetonitrile, pH 5.3) overnight at 37 degrees C. The target drugs were separated and quantified using a Waters ACQUITY UPLC coupled to a Waters Micromass LCT Premier XE Time-of-Flight mass spectrometer. Total chromatographic run time was 17min. The data were treated with the MassLynx software ChromaLynx XS and QuanLynx for automated identification and quantification, respectively. The limits of detection ranged from 0.01 to 0.10 ng/mg using a 10-mg hair sample and the limit of quantification was 0.05 ng/mg for 87% of the analytes. A good linear behaviour was achieved for most of the analytes in the range from LOQ to 10 or 25 ng/mg except for the amphetamines. The method showed an acceptable precision and trueness, since the obtained CV and BIAS values were <or=25% for 81% of the analytes. The extraction recoveries for 92% of the analytes ranged between 84 and 106% and the extraction recoveries for all analytes were better than 60%. The method was applied to 15 autopsy hair samples from forensic investigations showing a wide abuse pattern of many pharmaceuticals and drugs of abuse within a period of less than three months. The present study demonstrated that the combination of accurate mass and retention time can provide good selectivity, which demonstrates that the TOF instrument is adequate for both screening and quantification purposes. Furthermore, it was shown that screening with the ChromaLynx XS software is less sensitive and selective for some analytes than the QuanLynx software, especially in low concentrations.

Distribution Patterns, Dermatomal Anesthesia, and Ropivacaine Serum Concentrations After Bilateral Dual Transversus Abdominis Plane Block

Background and Objectives The ability of transversus abdominis plane (TAP) blocks to anesthetize the upper abdomen remains debatable. We aimed to describe the local anesthetic distribution following ultrasound-guided TAP blocks with repeated magnetic resonance imaging investigations and to relate this to the resulting dermatomal anesthesia. Methods Eight volunteers were included in a randomized, observer-blinded study. Sixty milliliters of ropivacaine 0.375% was administered: 1 injection of 30 mL as a lateral classic TAP block, followed by a sham upper intercostal TAP block, and on the contralateral side, 2 separate 15-mL injections at the upper intercostal and lateral classic TAP plexuses, respectively. The primary outcome measure was magnetic resonance imaging–assessed area expansion of all injectates over a 6-hr period. Dermatomal anesthesia and sequential serum ropivacaine levels were recorded at the same time intervals. Results All injectate areas expanded in a statistically significant manner in the anterior abdominal wall. Lateral classic TAP blocks with 30-mL injectates did not extend into the upper intercostal TAP plexus. The dual 15-mL injectates on the other hemiabdomen remained within the upper intercostal and lateral classic TAP compartments and resulted in significantly (P < 0.018) more widespread dermatomal anesthesia. Measured serum ropivacaine concentrations were below the potential level of toxicity. Conclusions Magnetic resonance imaging analysis revealed a significant time-dependent expansion of injectates. Magnetic resonance imaging and the degree of dermatomal anesthesia confirmed that the upper and lateral TAP compartments do not appear to communicate. Separate injections at the upper intercostal and lateral classic TAP plexuses are necessary to block the entire abdominal wall.

Screening for illicit and medicinal drugs in whole blood using fully automated SPE and ultra‐high‐performance liquid chromatography with TOF‐MS with data‐independent acquisition

A broad forensic screening method for 256 analytes in whole blood based on a fully automated SPE robotic extraction and ultra-high-performance liquid chromatography (UHPLC) with TOF-MS with data-independent acquisition has been developed. The limit of identification was evaluated for all 256 compounds and 95 of these compounds were validated with regard to matrix effects, extraction recovery, and process efficiency. The limit of identification ranged from 0.001 to 0.1 mg/kg, and the process efficiency exceeded 50% for 73 of the 95 analytes. As an example of application, 1335 forensic traffic cases were analyzed with the presented screening method. Of these, 992 cases (74%) were positive for one or more traffic-relevant drugs above the Danish legal limits. Commonly abused drugs such as amphetamine, cocaine, and frequent types of benzodiazepines were the major findings. Nineteen less frequently encountered drugs were detected e.g. buprenorphine, butylone, cathine, fentanyl, lysergic acid diethylamide, m-chlorophenylpiperazine, 3,4-methylenedioxypyrovalerone, mephedrone, 4-methylamphetamine, p-fluoroamphetamine, and p-methoxy-N-methylamphetamine. In conclusion, using UHPLC-TOF-MS screening with data-independent acquisition resulted in the detection of common drugs of abuse as well as new designer drugs and more rarely occurring drugs. Thus, TOF-MS screening of blood samples constitutes a practical way for screening traffic cases, with the exception of δ-9-tetrahydrocannabinol, which should be handled in a separate method.

Postmortem Blood Concentrations of R‐ and S‐Enantiomers of Methadone and EDDP in Drug Users: Influence of Co‐Medication and P‐glycoprotein Genotype

Abstract:  We investigated toxicological and pharmacogenetic factors that could influence methadone toxicity using postmortem samples. R‐ and S‐methadone were measured in femoral blood from 90 postmortem cases, mainly drug users. The R‐enantiomer concentrations significantly exceeded that of the S‐enantiomers (Wilcoxon’s test, p < 0.001). The samples were divided into four groups according to other drugs detected (methadone only, methadone and strong analgesics, methadone and benzodiazepines, or methadone and other drugs). There was no significant difference in any of the R‐methadone/total methadone ratios among the four groups. The median R/S ratio was 1.38, which tends to be higher than that reported for the plasma of living subjects. In addition, we investigated whether small nucleotide polymorphisms in the MDR1 gene that encode the drug transporter P‐glycoprotein were associated with the concentrations of R‐ and S‐methadone and its metabolite 2‐ethylidene‐1,5‐dimethyl‐3,3‐diphenylpyrrolidine. No significant association was detected.

Dominance of pre-analytical over analytical variation for measurement of methadone and its main metabolite in postmortem femoral blood

On the basis of simultaneously sampled postmortem blood specimens from the left and right femoral veins the pre-analytical variation of methadone measurements was evaluated and compared to the analytical variation. The material consisted of a series of 27 duplicate samples from routine autopsy cases comprising mainly drug addicts. A chiral LC-MS/MS method was used for measurement of the R- and S-enantiomers of methadone and its main metabolite 2-ethyl-1,5-dimethyl-3,3-diphenylpyrrolinium (EDDP). The analytical CV% was determined to be in the range 3-4% for methadone enantiomers and 4-6% for EDDP enantiomers. The total measurement uncertainty (CV(T)) was estimated from the pre-analytical variation (CV(PA)), analytical variation proper (CV(A)), and variation related to calibration (traceability) (CV(Cal)) according to the relationship CV(T) = [CV(2)(PA) + CV(2)(A) + CV(2)(cal)](0.5). Uncertainty related to calibration concerned a component related to the purity of drug reference compound and a contribution from the production of calibrator solutions (CV(Cal)<1%). Pre-analytical sampling variation was estimated from the duplicate measurements of blood samples after subtraction of the analytical component. The pre-analytical variation amounted to a CV% of 19-21% for R- and S-methadone and 30-38% for R- and S-EDDP, i.e. considerably larger than the other components. Due to the squared addition principle, the resulting total uncertainty (CV(T)) became largely identical to the CV(PA), i.e. 19-21% for R- and S-methadone and 31-38% for R- and S-EDDP enantiomers. Accordingly, CV(T) exceeded CV(A) by a factor 5 or more. Dominance of the pre-analytical component of variation may also be likely for other compounds measured in postmortem blood samples. Thus, the width of the 95%-uncertainty interval (+/-2CV(T)) for a postmortem measurement is largely determined by the pre-analytical component of variation. This should be kept in mind when judging on the uncertainty of postmortem measurement results.

A fatal case of amlodipine poisoning

A fatal overdose of amlodipine, a calcium channel blocker, in a 50-year-old man is described. Biological samples obtained at autopsy were screened for common drugs and narcotics. The amlodipine determination was made by HPLC with diode-array detection and a post-mortem blood concentration of 2.3 mg/kg was determined. The only other drug detected was a blood alcohol concentration of 0.008%. The presence of amlodipine was confirmed in other tissues and in the stomach content. The overdose is assumed to be an accumulation of amlodipine due to the long half-life of this drug.

Simultaneous Determination of 25 Common Pharmaceuticals in Whole Blood Using Ultra-Performance Liquid Chromatography–Tandem Mass Spectrometry

An ultra-performance liquid chromatography-tandem mass spectrometry method was developed and validated for the quantification of 25 common pharmaceuticals in whole blood. The selected pharmaceuticals represent the most frequently detected drugs in our forensic laboratory with basic properties such as analgesics, antidepressants, antihistamines, antihypertensives, antipsychotics and β-blockers. Whole blood samples were extracted with butyl acetate after adjusting pH with 2M NaOH. The target analytes were separated on a 100 × 2.1 mm ACQUITY BEH 1.7 µm C18 column by a formic acid/acetonitrile gradient elution using a Waters ACQUITY Ultra-Performance Liquid Chromatography system. Quantification was performed on a Waters tandem quadrupole ACQUITY TQD using multiple reaction monitoring in positive mode. The analytes were eluted within 11 min. The limit of quantification (LOQ) ranged from 0.002 to 0.01 mg/kg depending on the analyte. A good linear behavior was achieved for all analytes in the range from LOQ to 1.0 or 2.0 mg/kg blood. The absolute recoveries were between 55-87% for all compounds except norfluoxetine (44%). The method showed acceptable precision and accuracy for almost all analytes. Only unstable compounds like levomepromazine, methylphenidate, mirtazapine, norfluoxetine and zuclopenthixol deviated more. The method was successfully applied to more than 200 authentic blood samples within a year from forensic investigations.

Determination of amphetamine, methamphetamine, MDA and MDMA in human hair by GC-EI-MS after derivatization with perfluorooctanoyl chloride

The aim of this study was to develop a quantitative gas chromatography mass spectrometry (GC‐MS) method to determine the classical amphetamines and their methylenedioxylated derivatives in human hair. The procedure involved liquid–liquid extraction of hydrolysed hair spiked with deuterated internal standards and direct derivatization with perfluorooctanoyl chloride. After evaporation of the organic phase and dissolution in butylacetate, the derivatized compounds were injected into a GC‐MS. Method validation results showed a linear range from 0.25 to 25 ng/mg for the target compounds: amphetamine (AM), methamphetamine (MA), methylenedioxyamphetamine (MDA) and methylenedioxymethamphetamine (MDMA or ecstasy). An intra‐day precision of 3–6 % RSD and an inter‐day precision of 3–17 % RSD were observed. Trueness was between 96 % and 106 % for the target compounds. The limit of detection ranged from 0.07 to 0.14 ng/mg and of quantification from 0.24 to 0.46 ng/mg, depending on compound. The method was applied on 40 authentic hair samples (segmented or pooled hair), of which 15 cases involved amphetamine and/or ecstasy. The hair concentrations ranged from LOD to 3.2 ng/mg of AM in 7 cases, to 0.4 ng/mg of MDA in 3 cases and to 5.9 ng/mg of MDMA in 13 cases. MA was only detected once at trace level. The method, including the derivatization procedure, is simple and robust with a sensitivity that is satisfactory for measurement of amphetamines and ecstasy in hair from abusers.

Postmortem Quetiapine Reference Concentrations in Brain and Blood

Brain tissue is a useful alternative to blood in postmortem forensic investigations, but scarcity of information on reference concentrations in brain tissue makes interpretation challenging. Here we present a study of 43 cases where the antipsychotic drug quetiapine was quantified in brain tissue and related to concentrations in postmortem blood. For cases, where quetiapine was unrelated to the cause of death (N = 36), the 10-90 percentiles for quetiapine concentrations in brain tissue were 0.030-1.54 mg/kg (median 0.48 mg/kg, mean 0.79 mg/kg). Corresponding blood 10-90 percentile values were 0.007-0.39 mg/kg (median 0.15 mg/kg, mean 0.19 mg/kg), giving brain-blood ratio 10-90 percentiles of 2.31-6.54 (median 3.87, mean 4.32). Both correspond well to the limited amount of data found in the literature. For cases where quetiapine was a contributing factor to death (N = 5), the median value in brain tissue of 8.02 mg/kg (range 2.69-22.98 mg/kg) was more than 15 times higher than the median of the nontoxic values, and about the same relationship occurred for blood with a median of 3.19 mg/kg (range 1.00-6.90 mg/kg). The brain-blood ratios for toxic concentrations were in the range of 2.08-6.05, which correspond to those of the nontoxic concentrations. A single case, where quetiapine was ruled as the sole cause of death, a suicide by quetiapine overdose, had an even higher value of 25.74 mg/kg in brain tissue. The blood concentration was 8.99 mg/kg, giving a brain-blood ratio of 2.86. Thus, on average the brain concentrations were about four times the blood concentrations. The brain concentrations of quetiapine observed in cases, where quetiapine was unrelated to death, may serve as a reference, when evaluating postmortem cases with no blood available. The recorded concentrations, where quetiapine was contributing to death, give an indication of likely toxic concentrations.

Drug facilitated sexual assault with lethal outcome: GHB intoxication in a six-year-old girl.

A very serious case of DFSA (drug facilitated sexual assault) is presented, in which a six-year-old girl died following sedation with γ-hydroxybutyric acid (GHB). She had been sexually abused by a relative. Samples of cardiac blood, bile, vitreous humour, liver, kidney, brain tissues and hair were analysed by a LC-MS/MS method. The following GHB concentrations were determined: cardiac blood: 150 mg/l; bile: 292mg/l; vitreous humour: 58mg/l; liver: 100 mg/kg; kidney: 124.5 mg/kg, brain: 110 mg/kg. Very high GHB levels were found in the proximal part of the hair sample (about 40.9 ng/mg). In distal segments of hair - up to 12 cm distant from the hair scalp - GHB concentrations were higher than the overall found endogenous range of 2-3 ng/mg. Police investigations revealed that the uncle had also administered GHB to the older half-sister. Therefore, a sample of her hair was analysed accordingly, but unremarkable results were obtained. Comparing our toxicological results with police investigations and the offenders statements it can be assumed that the 6-year-old girl had ingested GHB. By exclusion of other causes of death a lethal intoxication with GHB could be confirmed.