1,720,971 research outputs found
Drugs of abuse analysis in urine and hair for the evaluation of the driving fitness. An epidemiological study
Full text linkLa guida sotto l’effetto di sostanze stupefacenti rappresenta un grave problema per la sicurezza stradale. La legge Italiana vieta il rilascio o la conferma della patente di guida a chiunque si trovi in stato di dipendenza o faccia un consumo abituale di sostanze stupefacenti o psicotrope. Ciò ha rilevanti ripercussioni sul piano sociale e professionale, dal momento che oggi la patente di guida è diventato uno strumento essenziale, oltre che per la mobilità, anche per lo svolgimento di numerose attività professionali. La normativa prevede che la valutazione di queste condizioni di consumo abituale e/o di dipendenza da sostanze d'abuso sia affidata alle commissioni mediche provinciali per le patenti, che si avvalgono di accertamenti chimico-tossicologici eseguiti sulle urine e/o sui capelli. Questo studio si è proposto di analizzare i risultati degli accertamenti chimico-tossicologici effettuati, su richiesta della Commissione Medica Provinciale per le patenti di Verona, dal laboratorio di Tossicologia Forense del Dipartimento di Sanità Pubblica e Medicina di Comunità dell'Università di Verona con l’obiettivo di: (i) valutare frequenze relative di positività ed eventuali trend per le diverse classi di sostanze d’abuso nel periodo 2003-2008; (ii) definire, nell’ambito della popolazione esaminata, i principali fattori di rischio per la positività all'accertamento; (iii) identificare l’approccio diagnostico più efficace per la valutazione di idoneità alla guida in rapporto all’uso di droga.
Durante il periodo esaminato la cocaina è stata in assoluto la sostanza stupefacente riscontrata più frequentemente. Il confronto tra l'analisi delle urine e dei capelli ha confermato la complementarietà delle due matrici biologiche e, dunque, la necessità di effettuare entrambe le analisi al fine di massimizzare la sensibilità epidemiologica dell'accertamento. Questo studio ha inoltre dimostrato come l'accertamento di idoneità alla guida costituisca un efficace deterrente al consumo di droghe dal momento che soltanto circa un quarto dei soggetti positivi al primo controllo risulta nuovamente positivo al secondo controllo.Driving under the influence of drugs is a serious problem for road traffic safety. According to the Italian Road Traffic Code, the driving licence must not be issued to anyone who abuses, is addicted to, or suffers for dependence to illicit or psychotropic drugs. The diagnosis of such clinical conditions is performed by Provincial Medical Commissions of the Public Health Service also on the basis of drugs of abuse testing results on urine and/or hair samples. This study aimed at examining test results obtained by the Forensic Toxicology laboratory of the Department of Public Health & Community Medicine, University of Verona, upon request of the local Medical Commission, over the period 2003-2008 with the purposes of (i) defining trends in drug abuse in the examined population (ii) identifying specific risk factors for testing positive and for relapse, (iii) selecting the most effective and efficient analytical strategy to detect illicit drugs use.
During the study period, cocaine was the most frequently detected illicit drug. The comparison of results from urine and hair testing confirmed the complementary features of these two biological substrates and the importance to have both data in order to increase the sensitivity in detecting illicit drug use. Moreover, this study showed that testing for driving fitness is an effective deterrent to illicit drug use, as only about one quarter of subjects testing positive at the first testing are still positive at the second testing
Dextromethorphan/levomethorphan issues in a case of opiate overdose.
No full textThe paper reports the case of a heroin addict who was found dead at his home with a fresh puncture mark on his leftarm. The GC-MS analysis of post-mortem blood and of the content of the syringe found next the body showed the presence of heroin and methorphan, probably used as adulterant of heroin. However GC-MS method was not able to distinguish between the two methorphan enantiomers, which show different pharmacological activity. To solve this problem, a chiral method based on the use of capillary electrophoresis with cyclodextrins was developed. The method was successfully applied to the analysis of the postmortem blood identifying the presence of dextromethorphan at a concentration of 842 ng/mL
Screening for pharmaco-toxicologically relevant compounds in biosamples using high-resolution mass spectrometry: a 'metabolomic' approach to the discrimination between isomers
No full textHigh-resolution mass spectrometry (HRMS) enables the identification of a chemical formula of small molecules through the accurate measurement of mass and isotopic pattern. However, the identification of an unknown compound starting from the chemical formula requires additional tools: (1) a database associating chemical formulas to compound names and (2) a way to discriminate between isomers. The aim of this present study is to evaluate the ability of a novel 'metabolomic' approach to reduce the list of candidates with identical chemical formula. Urine/blood/hair samples collected from real positive cases were submitted to a screening procedure using ESI-MS-TOF (positive-ion mode) combined with either capillary electrophoresis or reversed phase liquid chromatography (LC). Detected peaks were searched against a Pharmaco/Toxicologically Relevant Compounds database (ca 50 500 compounds and phase I and phase II metabolites) consisting of a subset of PubChem compounds and a list of candidates was retrieved. Then, starting from the mass of unknown, mass shifts corresponding to pre-defined biotransformations (e.g. demethylation, glucuronidation, etc.) were calculated and corresponding mass chromatograms were extracted from the total ion current (TIC) in order to search for metabolite peaks. For each candidate, the number of different functional groups in the molecule was automatically calculated using E-Dragon software (Talete srl, Milan, Italy). Then, the presence of metabolites in the TIC was matched with functional groups data in order to exclude candidates with structures not compatible with observed biotransformations (e.g. loss of methyl from a structure not bearing methyls). The procedure was tested on 108 pharmaco-toxicologically relevant compounds (PTRC) and their phase I metabolites were detected in real positive samples. The mean list length (MLL) of candidates retrieved from the database was 7.01 +/- 4.77 (median, 7; range, 1-28) before the application of the 'metabolomic' approach, and after the application it was reduced to 4.08 +/- 3.11 (median 3, range 1-17). HRMS allows a much broader screening for PTRC than other screening approaches (e.g. library search on mass spectra databases). The 'metabolomic' approach enables the reduction of the list of candidate isomers
Chiral CE to unravel “Methorphan dilemma”
No full textChiral analysis of methorphan and its major metabolites by CD-CZE in postmortem bloo
Chiral analysis of methorphan in opiate-overdose related deaths by using capillary electrophoresis
No full textAn enantioselective CE-based determination of methorphan and its main metabolites in blood is described. Enantiomeric separations were carried out in 50cm×50μm (ID) uncoated fused silica capillaries, using a background electrolyte composed of 150mM sodium phosphate pH 4.4 added with 5mM 2-(hydroxypropyl)-β-cyclodextrin and methanol 20% (v/v), at a constant voltage of 25kV. Sample injections were performed under field amplified sample stacking conditions. Detection was by recording UV absorbance at the wavelength of 200nm. Linearity of response was assessed within a concentration range from 25 to 500ng/mL for dextrometorhan, levomethorphan and their main metabolites (namely dextrorphan and levorphanol, respectively). Folcodine was used as internal standard. Under these conditions, the limit of quantification resulted 25ng/mL for each one of the analytes. The intra-day and inter-day precision, in terms of coefficient of variation (CV) were below 3.7% and 14.9 % for migration times and peak areas, respectively. The present method was successfully applied to the analysis of post-mortem blood samples from ten subjects died for heroin overdoses. Among the samples "positive" for methorphan (n=4), the d-enantiomer was found in concentrations ranging from 214 to 1282ng/mL. The concentration of its main metabolite dextrorphan in the same samples ranged from 49 to 389ng/mL
Calculation of LogP based on migration data in MEKC: application to the new synthetic cannabinoids.
No full textSince 2004, a number of “herbal blends” containing synthetic cannabinoid analogues have
appeared in the market, as a form of “legal” alternatives to Cannabis. These products are
available online through the “e-commerce” and in “smart shops” under several forms and various
brand names. A particular warning related to the diffusion of synthetic cannabinoids is based
on one hand on their high toxicological potential, and on the other hand on the insensitivity of
the current screening tests for cannabis towards these molecules. Moreover, because of their
recent introduction, the literature regarding these compounds is still limited. In particular any
experimental information on their octanol/water partition coefficient (logP) values is still lacking.
Indeed, hydrophobicity value is an important parameter to investigate drug absorption,
bioavailability and metabolism of molecules, as well as their toxicity. As a measure of molecular
hydrophobicity, the logarithm of the partition coefficient between 1-octanol and water (logP) is
widely used. The aim of the present study was to calculate the LogP of synthetic cannabinoids
by using micellar electrokinetic chromatography (MEKC) with UV detection. Samples were
analyzed using a fused silica capillary (30 mm x 40 cm) and a 25 mM sodium borate buffer pH
8, containing30 mMSDS and n-propanol 20%. After having constructed a calibration line using
10 appropriate standards with known LogP, an EOF marker and a micelle marker, a good
correlation was found between the MEKC retention data of further 5 compounds with known
LogP. The same calibration line was used to calculate the unknown LogP of the new synthetic
cannabinoids, namely JWH-200, AM-694, JWH-250, JWH-073, JWH-015, JWH-018, JWH-081,
JWH-122, JWH-019, JWH-210. The resulting Log P were in the range from 2.9 to 5.15. An
acceptable agreement was found between the experimental data and a few LogP values
calculated with XLogP3-AA reported in the literature
Use of synthetic cannabinoids to cheat the toxicological screenings
No full textUse of synthetic cannabinoids to cheat the toxicological screening
Finger-prick dried blood spot and capillary electrophoresis: a challenge for alcohol abusers screening analysis
No full textIntroduction and aimFinger-prick related DBS (fpDBS) is a new and innovative specimen collection in clinical practice to develop a screening method for forensic toxicology study [1].Despite this, still very limitedly employed is the fpDBS specimens for capillary electrophoresis (CE) analyses. Transferrin glycoforms are a suitable parameter in alcohol abuse investigation and in particular the carbohydrate deficient transferrin (CDT), defined as the percentage distribution of less glycosilated transferrin, is increased after chronic sustained alcohol intake [2]. The aim of this study was to verify if the use of fpDBS could be suitable for CDT screening CE analysis. MethodHuman serum specimens were collected from volunteer subjects. fpDBS sample collection was performed by pricking the little finger, absorbing the capillary blood drops on DBS cards and letting it to air dry. Once dried, samples required a treatment, which included three easy steps: A) sample resuspension from fpDBS with an acid solution (to remove interfering circulating proteins, mainly haemoglobin); B) removing the paper from the sample solution and pH check (3<4); C) sample neutralization (pH 7-8). The final sample was centrifuged and the supernatant was diluted with an iron rich solution before CE analysis. The CE running buffer was borate (pH 7.9) with diaminobutane (7.5 mmol/L), and the separations were performed within a 30 μm i.d. uncoated fused-silica capillary (length 60cm) using a constant voltage (30kV) and detection at 200 nm. The study was executed analysing fpDBS and parallel serum samples collected from each investigated subject and ÍT levels were measured using both high performance liquid chromatography (HPLC) and CE techniques.Results and conclusionThe comparison between fpDBS and parallel serum CDT level, analysed by the traditional CE and HPLC methods, demonstrated significant correlation r2>0.85. In addition, statistical analysis confirmed that the concentration differences measured in DBS specimens were not relevant. Our results demonstrate how the acid treatment allows analysis in CE despite the small volumes and the large amount of various interfering compounds of whole blood. Therefore, the CE technique use coupled to the fpDBS procedure for CDT analysis expresses a simplified and inexpensive tool designed for use in population screening. In conclusion, the fpDBS CE procedure appear suitable in the forensic alcohol abuse investigations.References[1] CP Stove, AS Ingels, PM De Kesel, WE Lambert. Crit Rev Toxicol. 42 (2012) 230-43.[2] JR Delanghe, ML De Buyzere. Clin Chim Acta. 406 (2009) 1-7
Strategie analitiche alternative per lo studio dell’abuso alcolico cronico nel cadavere mediante Carbohydrate Deficient Transferrin (CDT)
No full textAbstrac
Fluorescent adduct formation with terbium: a novel strategy for transferrin glycoform identification in human body fluids and carbohydrate-deficient transferrin HPLC method validation
No full textThis paper puts forward a new method for the transferrin (Tf) glycoform analysis in body fluids that involves the formation of a transferrin-terbium fluorescent adduct (TfFluo). The key idea is to validate the analytical procedure for carbohydrate-deficient transferrin (CDT), a traditional biochemical serum marker to identify chronic alcohol abuse. Terbium added to a human body-fluid sample produced TfFluo. Anion exchange HPLC technique, with fluorescence detection (λ exc 298 nm and λ em 550 nm), permitted clear separation and identification of Tf glycoform peaks without any interfering signals, allowing selective Tf sialoforms analysis in human serum and body fluids (cadaveric blood, cerebrospinal fluid, and dried blood spots) hampered for routine test. Serum samples (n = 78) were analyzed by both traditional absorbance (Abs) and fluorescence (Fl) HPLC methods and CDT% levels demonstrated a significant correlation (p < 0.001 Pearson). Intra- and inter-runs CV% was 3.1 and 4.6%, respectively. The cut-off of 1.9 CDT%, related to the HPLC Abs proposed as the reference method, by interpolation in the correlation curve with the present method demonstrated a 1.3 CDT% cut-off. Method comparison by Passing-Bablok and Bland-Altman tests demonstrated Fl versus Abs agreement. In conclusion, the novel method is a reliable test for CDT% analysis and provides a substantial analytical improvement offering important advantages in terms of types of body fluid analysis. Its sensitivity and absence of interferences extend clinical applications being reliable for CDT assay on body fluids usually not suitable for routine test. Graphical Abstract The formation of a transferrin-terbium fluorescent adduct can be used to analyze the transferrin glycoforms. The HPLC method for carbohydrate-deficient transferrin (CDT%) measurement was validated and employed to determine the levels in different body fluids
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