Mário Dias

Liquid chromatography/tandem mass spectrometry for the qualitative and quantitative analysis of illicit drugs and medicines in preserved oral fluid

A qualitative and quantitative analytical method was developed for the simultaneous determination of 24 illicit drugs and medicines, in preserved oral fluid samples collected with the StatSure Saliva Sampler collection device. The samples were prepared by liquid-liquid extraction followed by liquid chromatography/tandem mass spectrometry (LC/MS/MS) analysis. The chromatographic separation was performed with an Atlantis T3 (100 x 2.1 mm i.d., 3 microm) reversed-phase column using an acetonitrile/2 mM ammonium formate buffer pH 3.4 gradient and the MS/MS detection was achieved with two precursor-product ion transitions per substance. The method was fully validated, including specificity and capacity of identification, limit of detection (0.2-2.1 microg/L), limit of quantitation (0.8-6.4 microg/L), recovery (34-98%), carryover, linearity (the method was linear in the range 1-200 microg/L), intra-assay precision (coefficient of variance (CV) <20% for 20 microg/L and CV <10% for 100 microg/L) and inter-assay accuracy (mean relative error <15%) and precision (CV <20%). The method showed to be specific and sensitive. It has already been successfully used in four proficiency tests and subsequently applied to oral fluid samples collected from road traffic volunteers in the driving population of Portugal (districts of Lisbon, Coimbra and Porto), within the DRUID project.

Validation and application of an UPLC-MS/MS method for the quantification of synthetic cannabinoids in urine samples and analysis of seized materials from the Portuguese market.

An UPLC-MS/MS method using ESI+ionization and MRM was developed and fully validated according to international guidelines for the qualitative and quantitative analysis of nine synthetic cannabinoids and/or their metabolites in urine samples (1mL). Prior to extraction the samples were subjected to an enzymatic hydrolysis using β-glucuronidase followed by a SPE procedure using Oasis(®) HLB 3cc (60mg) columns. The chromatographic separation was performed with an Acquity UPLC(®) HSS T3 (50mm×2.1mm i.d., 1.8μm) reversed-phase column using a gradient with methanol-ammonium formate 2mM (0.1% formic acid) and with a run time of 9.5min. The method was validated in terms of selectivity, capacity of identification, limits of detection (0.01-0.5ng/mL) and quantification (0.05-0.5ng/mL), recovery (58-105%), carryover, matrix effect, linearity (0.05-50ng/mL), intra-assay precision, inter-assay accuracy and precision (CV<20%). The method was applied to 80 authentic samples, five of them (6.2%) were confirmed or suspected to be positive for the metabolites JWH-018 N-hydroxypentyl and JWH-018 N-pentanoic acid of JWH-018 and for the metabolite JWH-122 N-(5-hydroxypentyl) of JWH-122, and three of them in association with THC and/or THCCOOH (substances included in the method, together with the 11-OH-THC). Additionally, 17 spice products were analyzed, for which were confirmed the presence of the following substances: AM-2201, JWH-018, JWH-022 JWH-073, JWH-122, JWH-203, JWH-210, JWH-250, HU-210 and RCS-4, according to the comparison with authentic reference material and published data. The analytical method developed allowed the analysis of synthetic cannabinoids and the notification of the first cases in Portugal.

Prevalence of alcohol, illicit drugs and psychoactive medicines in killed drivers in four European countries

Our objective was to determine the presence of psychoactive substances in blood of drivers killed in road crashes in four European countries. Data from 1118 drivers of car and vans, killed between 2006 and 2009, were collected in Finland, Norway, Portugal and Sweden. The prevalence of any psychoactive substance ranged between 31 and 48%. Alcohol (≥ 0.1 g/L) was the most common finding, 87% had a blood alcohol concentration (BAC) ≥ .5 g/L. Benzodiazepines (1.8–13.3%) and amphetamines (0–7.4%) were the most prevalent psychoactive medicines and illicit drugs, respectively. Alcohol–drug and drug–drug combinations were rather prevalent. Differences in alcohol/drug findings seemed to reflect differences in use in the countries. More research should be done to develop preventive strategies to reduce the number of alcohol- and drug-related traffic accidents targeting at-risk groups, such as drivers with very high BACs and novice drivers.

Qualitative and quantitative analysis of THC, 11-hydroxy-THC and 11-nor-9-carboxy-THC in whole blood by ultra-performance liquid chromatography/tandem mass spectrometry.

A qualitative and quantitative analytical method was developed for the simultaneous determination of Δ(9) -tetrahydrocannabinol (THC), 11-hydroxy-Δ(9) -tetrahydrocannabinol (11-OH-THC) and l1-nor-9-carboxy-Δ(9) -tetrahydrocannabinol (THC-COOH) in whole blood. The samples were prepared by solid-phase extraction followed by ultra-performance liquid chromatography/tandem mass spectrometry (UPLC/MS/MS) analysis using positive ion electrospray ionization and multiple reaction monitoring. The chromatographic separation was performed with an Acquity UPLC® HSS T3 (50 × 2.1 mm i.d., 1.8 µm) reversed-phase column using a methanol/2 mM ammonium formate (formic acid 0.1%) gradient in a total run time of 9.5 min. MS/MS detection was achieved with two precursor-product ion transitions per substance. The method was fully validated, including selectivity and capacity of identification, according to the identification criteria (two transitions per substance, signal-to-noise ratio, relative retention time and ion ratio) without the presence of interferences, limit of detection (0.2 µg/L for THC and 0.5 µg/L for 11-OH-THC and THC-COOH), limit of quantitation (0.5 µg/L for all cannabinoids), recovery (53-115%), carryover, matrix effect (34-43%), linearity (0.5-100 µg/L), intra-assay precision (CV < 10% for the relative peak area ratios and <0.1% for the relative retention time), inter-assay accuracy (mean relative error <10%) and precision (CV <11%). The method has already been successfully used in proficiency tests and subsequently applied to authentic samples in routine forensic analysis.

Dried blood spots combined to an UPLC–MS/MS method for the simultaneous determination of drugs of abuse in forensic toxicology

HighlightsA DBS‐UPLC–MS/MS method is proposed for drugs of abuse analysis in forensic toxicology.The method shows small run time, high sensitivity, very good precision and accuracy.The storage stability of all the substances in the DBS was demonstrated.Real samples analysis revealed a good correlation between DBS and WB results.The method developed emphasizes the potential of using the DBS for forensic analysis. ABSTRACT A method for the simultaneous determination of 11 illicit drugs, using the dried blood spot (DBS) sampling technique combined with the UPLC–MS/MS technology was developed to study its applicability within the forensic toxicology. The DBS samples, prepared from a blood volume of 50 &mgr;L and using the Whatman® BFC 180 bloodstain cards, were extracted with a methanol/acetonitrile mixture. The chromatographic separation was performed using an Acquity UPLC® HSS T3 column (100 mm × 2.1 mm, 1.8 &mgr;m) and an acetonitrile/2 mM ammonium formate (0.1% formic acid) gradient. The detection was accomplished with a TQ Detector, operating in the ESI+ and MRM modes. The method was validated in terms of selectivity, matrix effect, extraction recovery (42%–91%), carryover, LOD and LOQ (0.5–1 ng/mL and 1–5 ng/mL, respectively), linearity (LOQ to 500 ng/mL), intraday and interday precision (3.8–14% and 5.3–13%, respectively), accuracy (−9.3% to 7.9%) and dilution integrity. An eight months stability study at room temperature, 2–8 °C and −10 °C, was also performed, with the best results obtained at −10 °C. The procedure was applied to 64 real samples (92 positive results for substances included in this study). The results were compared with the methodologies routinely applied in the laboratory and the statistical analysis allowed to establish an acceptable correlation. This study permitted to determine that the DBS can represent an alternative or a complement to conventional analytical and sampling techniques, responding to some of the present issues concerning the different forensic toxicology applications.

Validated method for the determination of misoprostol acid in whole blood by ultra performance liquid chromatography-tandem mass spectrometry.

Misoprostol is a pharmaceutical synthetic compound, analog of prostaglandin E1, frequently used as an abortifacient in not medically supervised or self-induced abortions, particularly in countries with restrictive abortion laws representing a serious public health problem. The aim of this study was to develop and validate a sensitive analytical method for the determination of misoprostol acid in whole blood samples. The samples were prepared by SPE and the chromatographic separation was performed by UPLC-MS/MS using ESI- and MRM mode with an Acquity UPLC(®) BEH C18 (50mm×2.1mm i.d., 1.7μm) column using a methanol-ammonium 0.1% solution gradient in a total run time of 7.0min. The method showed to be selective and linear in range 25-2000ng/L. The LOD and LOQ were 10ng/L and 25ng/L, respectively. The recovery ranged from 89 to 97%. No carryover and significant matrix effect were observed. The intra- and inter-assay precisions and the inter-assay accuracy results were 4.0% and 5.4%, 5.5% and 4.1%, and -1.4% and -2.8%, for the concentrations 50 and 500ng/L, respectively. The method developed allows the analysis of misoprostol acid in whole blood samples with adequate sensitivity to the concentration range obtained from therapeutic doses. The method was successfully used in a controlled misoprostol administration study and has been applied in our laboratory in the forensic toxicology field.

Sequencing CYP2D6 for the detection of poor-metabolizers in post-mortem blood samples with tramadol

Tramadol concentrations and analgesic effect are dependent on the CYP2D6 enzymatic activity. It is well known that some genetic polymorphisms are responsible for the variability in the expression of this enzyme and in the individual drug response. The detection of allelic variants described as non-functional can be useful to explain some circumstances of death in the study of post-mortem cases with tramadol. A Sanger sequencing methodology was developed for the detection of genetic variants that cause absent or reduced CYP2D6 activity, such as *3, *4, *6, *8, *10 and *12 alleles. This methodology, as well as the GC/MS method for the detection and quantification of tramadol and its main metabolites in blood samples was fully validated in accordance with international guidelines. Both methodologies were successfully applied to 100 post-mortem blood samples and the relation between toxicological and genetic results evaluated. Tramadol metabolism, expressed as its metabolites concentration ratio (N-desmethyltramadol/O-desmethyltramadol), has been shown to be correlated with the poor-metabolizer phenotype based on genetic characterization. It was also demonstrated the importance of enzyme inhibitors identification in toxicological analysis. According to our knowledge, this is the first study where a CYP2D6 sequencing methodology is validated and applied to post-mortem samples, in Portugal. The developed methodology allows the data collection of post-mortem cases, which is of primordial importance to enhance the application of these genetic tools to forensic toxicology and pathology.

Sudden cardiac death a case with two distinct and unrelated causes

Res_eng:Cardiovascular diseases are the most frequent causes of Sudden Death in the adult. The authors report the case of a 44-year-old man who died sudden and unexpectedly when driving from Lisbon to Coimbra. A forensic postmortem examination revealed not only hypertensive and ischemic cardiopathy but also hypersensitivity non-illicit druginduced myocarditis, with morphological evidence of both mechanical and arrhythmic mechanisms leading to death. It highlights the relevance of histological examination in the investigation of sudden death and emphasizes the etiologic complexity underlying cardiac sudden, unexpected deaths.