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Ingels A.-S.M.E.,Ghent University | Ingels A.-S.M.E.,National Institute of Criminalistics and Criminology | Wille S.M.R.,National Institute of Criminalistics and Criminology | Samyn N.,National Institute of Criminalistics and Criminology | And 2 more authors.
Analytical and Bioanalytical Chemistry | Year: 2014

The purpose of this review is to provide a comprehensive overview of reported methods for screening and confirmation of the low-molecular-weight compound and drug of abuse gamma-hydroxybutyric acid (GHB) in biological fluids. The polarity of the compound, its endogenous presence, its rapid metabolism after ingestion, and its instability during storage (de novo formation and interconversion between GHB and its lactone form gamma-butyrolactone) are challenges for the analyst and for interpretation of a positive result. First, possible screening procedures for GHB are discussed, including colorimetric, enzymatic, and chromatography-based procedures. Confirmation methods for clinical and forensic cases mostly involve gas chromatography (coupled to mass spectrometry), although liquid chromatography and capillary zone electrophoresis have also been used. Before injection, sample-preparation techniques include (a combination of) liquid-liquid, solid-phase, or headspace extraction, and chemical modification of the polar compound. Also simple "dilute-and- shoot" may be sufficient for urine or serum. Advantages, limitations, and trends are discussed. © 2014 Springer-Verlag Berlin Heidelberg.

Van der Linden T.,Ghent University | Van der Linden T.,National Institute of Criminalistics and Criminology | Legrand S.-A.,Ghent University | Silverans P.,Belgian Road Safety Institute | Verstraete A.G.,Ghent University
Journal of Analytical Toxicology | Year: 2012

The objective of this study was to compare the number of drivers with drug concentrations above the legal cutoffs for driving under the influence of illicit substances in paired samples of blood and oral fluid. Between January 2008 and September 2009, 2,949 randomly selected drivers participated in a roadside survey. Each was asked to provide blood and oral fluid. Samples were analyzed for 11 illicit substances or metabolites by ultra-performance liquid chromatography-tandem mass spectrometry and gas chromatography- tandem mass spectrometry. Out of the 2,750 drivers who gave both blood and oral fluid, 28 (1.0%) had drug concentrations above the legal cutoff in blood and 71 (2.6%) were above the legal cutoff in oral fluid. Fifteen (7.5%) of the 199 drivers who gave an oral fluid sample but refused to provide blood tested positive, significantly more than drivers who provided both samples. Based on oral fluid analysis, 2.6 times more subjects tested positive for drugs compared to blood analysis. Those that refused to give a blood sample were 3 times more likely to test positive for drugs. Even in a survey that guaranteed total anonymity, people fearing a positive test result might have been more likely to refuse to give a blood sample. © The Author [2012]. Published by Oxford University Press. All rights reserved.

Jordaens K.,Royal Museum for Central Africa | Jordaens K.,University of Antwerp | Sonet G.,Royal Belgian Institute Of Natural Sciences | Richet R.,Grande Rue | And 3 more authors.
International Journal of Legal Medicine | Year: 2013

The identification of species of the forensically important genus Sarcophaga is very difficult and requires strong taxonomic expertise. In this study, we sequenced the mitochondrial cytochrome c oxidase subunit I (COI) gene of 126 specimens of 56 W European Sarcophaga species and added GenBank data to our database to yield a total dataset of 270 COI sequences from 99 Sarcophaga species to evaluate the COI gene as a molecular diagnostic tool for species identification in this genus. Using two simple criteria (Best Match, BM and Best Close Match, BCM), we showed that the identification success using a mini-barcode region of 127 bp was very low (80.7-82.5 %) and the use of this region is not recommended as a species identifier. In contrast, identification success was very high using the standard barcode region (658 bp) or using the entire COI region (1,535 bp) (98.2-99.3 %). Yet, there was a low interspecific sequence divergence (<2 %) in six species groups so that for 16 out of the 99 species (nine of which are of forensic importance), the use of COI barcodes as species identifier should be done with care. For these species, additional markers will be necessary to achieve a 100 % identification success. We further illustrate how such reference databases can improve local reference databases for forensic entomologists. © 2012 Springer-Verlag.

Desmyter S.,National Institute of Criminalistics and Criminology | Gijsbers L.,National Institute of Criminalistics and Criminology | Gijsbers L.,University of Amsterdam
Forensic Science International: Genetics | Year: 2012

In canine population studies for forensics, the mitochondrial DNA is profiled by sequencing the two hyper variable regions, HV1 and HV2 of the control region. In a first effort to create a Belgian population database some samples showed partially poor sequence quality. We demonstrated that a nuclear pseudogene was co-amplified with the mtDNA control region. Using a new combination of primers this adverse result was no longer observed and sequencing quality was improved. All former samples with poor sequence data were reanalyzed. Furthermore, the forensic canine population study was extended to 208 breed and mixed dogs. In total, 58 haplotypes were identified, resulting in an exclusion capacity of 0.92. The profile distribution of the Belgian population sample was not significantly different from those observed in population studies of three other countries. In addition to the total population study 107 Belgian registered pedigree dogs of six breeds were profiled. Per breed, the obtained haplotypes were supplemented with those from population and purebred studies. The combined data revealed that some haplotypes were more or less prominent present in particular dog breeds. The statistically significant differences in haplotype distribution between breeds and population sample can have consequences on mtDNA databasing and matching probabilities in forensics. © 2011 Elsevier Ireland Ltd. All rights reserved.

Fernandez M.D.M.R.,National Institute of Criminalistics and Criminology | Samyn N.,National Institute of Criminalistics and Criminology
Journal of Analytical Toxicology | Year: 2011

A fast and selective ultra-performance liquid chromatography- tandem mass spectrometry (UPLC-MS-MS) method for the determination of amphetamines (amphetamine, methamphetamine, methylenedioxymethamphetamine, methylenedioxyamphetamine, methylenedioxyethylamphetamine, ephedrine, and p-methoxyamphetamine) in plasma has been developed and validated. Sample preparation was performed by liquid-liquid extraction using ethyl acetate. For optimized chromatographic performance with repeatable retention times, narrow and symmetrical peaks, and focusing all analytes at the column inlet, a gradient start, with acid mobile phase consisting of 0.1% formic acid and methanol was chosen. Positive electrospray ionization MS-MS detection was performed with two multiple reaction monitoring transitions for each analyte. Deuteriumlabeled internal standards were used for five of the analytes. The limit of detection was in the range 0.25-1.25 ng/mL, and the limit of quantification was fixed at the lowest calibrator of 2.5 ng/mL for all of the compounds. The RSD values of the intra- and interassay precision and accuracy were lower than 11% at four concentration levels, including two external quality controls. No or only minor matrix effects were observed, and the extraction method presented recoveries higher than 93% for all the compounds. Total run time, including equilibration, was 12 min. The method is routinely used at the National Institute of Criminalistics and Criminology for quantitative determination of the main amphetamines in plasma from forensic and driving under the influence cases.

Ramirez Fernandez M.D.M.,National Institute of Criminalistics and Criminology | Wille S.M.R.,National Institute of Criminalistics and Criminology | Samyn N.,National Institute of Criminalistics and Criminology
Therapeutic Drug Monitoring | Year: 2012

A fast and selective ultraperformance liquid chromatographic-tandem mass spectrometric method was developed and validated for the simultaneous quantification of amitriptyline, citalopram, clomipramine, desipramine, desmethylcitalopram, desmethylclomipramine, desmethyldosulepin, desmethyldoxepin, desmethylfluoxetine, desmethylvenlafaxine, didesmethylcitalopram, dosulepin, doxepin, duloxetine, fluoxetine, fluvoxamine, imipramine, maprotiline, mianserin, mirtazapine, moclobemide, nortriptyline, paroxetine, reboxetine, sertraline, trazodone, and venlafaxine in 100 μL of plasma. After liquid-liquid extraction with 1-chlorobutane, analytes were separated on a BEH (Ethylene Bridged Hybrid) C18 analytical column with gradient elution. The compounds were ionized and detected over 7-minute analysis time by electrospray ionization tandem mass spectrometry with multiple reaction monitoring. Limits of quantification and limits of detection ranged from 2.5 to 10 ng/mL and 0.2 to 10 ng/mL, respectively. Intra- and interassay imprecision were lower than 15% for all the compounds except for mirtazapine, moclobemide, and desmethylclomipramine [relative standard deviation (RSD) < 20%], and the bias of the assay was lower than 15% for all the compounds except for fluvoxamine (bias < 20.5%), evaluated with 5 commercial quality control and 3 "in-house" quality control. The extraction was found to be reproducible (RSD < 16%) (except for duloxetine RSD 21.9%) and with recoveries varying from 59% to 86%. Furthermore, the stability studies demonstrated that the processed samples were stable in the autosampler for 24 hours for all the compounds. The method was successfully applied to the analysis of authentic samples from forensic toxicology cases and external quality control assays from the Society of Toxicology and Forensic Chemistry (GTFCh). The method was completely validated and can be of interest to clinical and forensic laboratories. Copyright © 2012 by LippincottWilliams & Wilkins.

Verscheure S.,National Institute of Criminalistics and Criminology | Verscheure S.,University of Antwerp | Backeljau T.,University of Antwerp | Backeljau T.,Royal Belgian Institute Of Natural Sciences | Desmyter S.,National Institute of Criminalistics and Criminology
Forensic Science International: Genetics | Year: 2014

A Belgian dog population sample and several population studies worldwide have confirmed that only a limited number of mtDNA control region haplotypes is observed in the majority of dogs. The high population frequency of these haplotypes negatively impacts both the exclusion probability of dog mtDNA analysis and the evidential value of a match with one of these haplotypes in casework. Variation within the mtDNA coding region was explored to improve the discrimination power of dog mtDNA analysis. In the current study, the entire mitochondrial genome of 161 dogs was sequenced applying a quality assured strategy and resulted in a total of 119 different mitochondrial genome sequences. Our research was focused on those dogs with the six most common control region haplotypes from a previous Belgian population study. We identified 33 informative SNPs that successfully divide the six most common control region haplotypes into 32 clusters of mitochondrial genome sequences. Determining the identity of these 33 polymorphic sites in addition to control region sequencing in case of a match with one of these 6 control region haplotypes could augment the exclusion probability of forensic dog mtDNA analysis from 92.5% to 97.5%. © 2014 Elsevier Ireland Ltd.

Wille S.M.R.,National Institute of Criminalistics and Criminology | Peters F.T.,University Hospital Jena | Di Fazio V.,National Institute of Criminalistics and Criminology | Samyn N.,National Institute of Criminalistics and Criminology
Accreditation and Quality Assurance | Year: 2011

Reporting reliable analytical data is the backbone of forensic and clinical bioanalytical research and applications. Therefore, international agreement concerning validation and quality control requirements is needed. Several international guidelines provide a standard for fundamental validation parameters such as selectivity, matrix effects, method limits, calibration, accuracy, precision and stability. However, it is not always easy for the analyst to 'translate' these guidelines into practice. International guidelines remain nonbinding protocols that need to be updated according to the type of application and the analyst's method requirements and depends on the evolution of analytical techniques. In this publication, suggestions for experimental set-up, statistical approaches and straightforward acceptance criteria for validation of forensic bioanalytical applications are suggested. Furthermore, permanent quality control, to ensure state-of-the-art quantitative analytical performances, as well as measurement uncertainty influencing interpretation is discussed. © 2011 Springer-Verlag.

Wille S.M.R.,National Institute of Criminalistics and Criminology | Di Fazio V.,National Institute of Criminalistics and Criminology | Ramirez-Fernandez M.D.M.,National Institute of Criminalistics and Criminology | Kummer N.,National Institute of Criminalistics and Criminology | Samyn N.,National Institute of Criminalistics and Criminology
Therapeutic Drug Monitoring | Year: 2013

BACKGROUND: "Driving under the influence of drugs" (DUID) has a large impact on the worldwide mortality risk. Therefore, DUID legislations based on impairment or analytical limits are adopted. Drug detection in oral fluid is of interest due to the ease of sampling during roadside controls. The prevalence of Δ-tetrahydrocannabinol (THC) in seriously injured drivers ranges from 0.5% to 7.6% in Europe. For these reasons, the quantification of THC in oral fluid collected with 3 alternative on-site collectors is presented and discussed in this publication. METHODS: An ultra-performance liquid chromatography-mass spectrometric quantification method for THC in oral fluid samples collected with the StatSure (Diagnostic Systems), Quantisal (Immunalysis), and Certus (Concateno) devices was validated according to the international guidelines. Small sample volumes of 100-200 μL were extracted using hexane. Special attention was paid to factors such as matrix effects, THC adsorption onto the collector, and stability in the collection fluid. RESULTS: A relatively high-throughput analysis was developed and validated according to ISO 17025 requirements. Although the effects of the matrix on the quantification could be minimized using a deuterated internal standard, and stability was acceptable according the validation data, adsorption of THC onto the collectors was a problem. For the StatSure device, THC was totally recovered from the collector pad after storage for 24 hours at room temperature or 7 days at 4 C. A loss of 15%-25% was observed for the Quantisal collector, whereas the recovery from the Certus device was irreproducible (relative standard deviation, 44%-85%) and low (29%-80%). During the roadside setting, a practical problem arose: small volumes of oral fluid (eg, 300 μL) were collected. However, THC was easily detected and concentrations ranged from 8 to 922 ng/mL in neat oral fluid. CONCLUSION: A relatively high-throughput analysis (40 samples in 4 hours) adapted for routine DUID analysis was developed and validated for THC quantification in oral fluid samples collected from drivers under the influence of cannabis. Copyright © 2013 by Lippincott Williams & Wilkins.

De Bock J.,National Institute of Criminalistics and Criminology | De Smet P.,National Institute of Criminalistics and Criminology
IEEE Transactions on Information Forensics and Security | Year: 2016

In this paper, we present a new tool for forensic recovery of single and multi-fragment JPEG/JFIF data files. First, we discuss the basic design and the technical methods composing our proposed data carving algorithm. Next, we compare the performance of our method with the well-known Adroit Photo Forensics (APF) state-of-the art tool. This comparison is centered on both the carving results as well as the obtained data processing speed, and is evaluated in terms of the results that can be obtained for several well-known reference data sets. Important to note is that we specifically focus on the fundamental recovery and fragment matching performance of the tools by forcing them to use various assumed cluster sizes. We show that on all accounts our new tool can significantly outperform APF. This improvement in data processing speed and carving results can be mostly attributed to novel methods to iterate and reduce the data search space and to a novel parameterless method to determine the end of a fragment based on the pixel data. Finally, we discuss several options for future research. © 2015 IEEE.

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