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1.
Drug Test Anal ; 2023 Nov 30.
Article in English | MEDLINE | ID: mdl-38037247

ABSTRACT

Synthetic cannabinoid receptor agonists (SCRAs) are a diverse class of new psychoactive substances (NPS) and new structural scaffolds have emerged on the recreational drug market since the enactment of Chinese SCRA analog controls in 2021. This study reports the first SCRAs to be detected with a bromide at the 5 position (5'Br) on the phenyl ring of the indazole core and without a tail moiety. ADB-5'Br-INACA (ADMB-5'Br-INACA) and MDMB-5'Br-INACA were detected in seized samples from Scottish prisons, Belgian customs, and US forensic casework. The brominated analog with a tail moiety, ADB-5'Br-BUTINACA (ADMB-5'Br-BUTINACA), was also detected in Scottish prisons and US forensic casework. The metabolites of these compounds and the predicted compound MDMB-5'Br-BUTINACA were identified through incubation with primary human hepatocytes to aid in their toxicological identification. The bromide on the indazole remains intact on metabolites, allowing these compounds to be easily distinguished in toxicological samples from their non-brominated analogs. Glucuronidation was more common for tail-less analogs than their butyl tail-containing counterparts. Forensic toxicologists are advised to update their analytical methods with the characteristic ions for these compounds, as well as their anticipated urinary markers: amide hydrolysis and monoOH at tert-butyl metabolites (after ß-glucuronidase treatment) for ADB-5'Br-INACA; monoOH at tert-butyl and amide hydrolysis metabolites for ADB-5'Br-BUTINACA; and ester hydrolysis metabolites with additional metabolites for MDMB-5'Br-INACA and MDMB-5'Br-BUTINACA. Toxicologists should remain vigilant to the emergence of new SCRAs with halogenation of the indazole core and tail-less analogs, which have already started to emerge.

2.
Forensic Sci Int ; 332: 111182, 2022 Mar.
Article in English | MEDLINE | ID: mdl-35074711

ABSTRACT

Unlike other more established disciplines, a shared understanding and broad acceptance of the essence of forensic science, its purpose, and fundamental principles are still missing or mis-represented. This foundation has been overlooked, although recognised by many forensic science forefathers and seen as critical to this discipline's advancement. The Sydney Declaration attempts to revisit the essence of forensic science through its foundational basis, beyond organisations, technicalities or protocols. It comprises a definition of forensic science and seven fundamental principles that emphasise the pivotal role of the trace as a vestige, or remnant, of an investigated activity. The Sydney Declaration also discusses critical features framing the forensic scientist's work, such as context, time asymmetry, the continuum of uncertainties, broad scientific knowledge, ethics, critical thinking, and logical reasoning. It is argued that the proposed principles should underpin the practice of forensic science and guide education and research directions. Ultimately, they will benefit forensic science as a whole to be more relevant, effective and reliable.

3.
Drug Test Anal ; 14(4): 634-652, 2022 Apr.
Article in English | MEDLINE | ID: mdl-34811926

ABSTRACT

Early warning systems detect new psychoactive substances (NPS), while dedicated monitoring programs and routine drug and toxicology testing identify fluctuations in prevalence. We report the increasing prevalence of the synthetic cannabinoid receptor agonist (SCRA) ADB-BUTINACA (N-[1-amino-3,3-dimethyl-1-oxobutan-2-yl]-1-butyl-1H-indazole-3-carbox-amide). ADB-BUTINACA was first detected in a seizure in Sweden in 2019, and we report its detection in 13 routine Swedish forensic toxicology cases soon after. In January 2021, ADB-BUTINACA was detected in SCRA-infused papers seized in Scottish prisons and has rapidly increased in prevalence, being detected in 60.4% of the SCRA-infused papers tested between January and July 2021. In this work, ADB-BUTINACA was incubated with human hepatocytes (HHeps), and 21 metabolites were identified in vitro, 14 being detected in authentic case samples. The parent drug and metabolites B9 (mono-hydroxylation on the n-butyl tail) and B16 (mono-hydroxylation on the indazole ring) are recommended biomarkers in blood, while metabolites B4 (dihydrodiol formation on the indazole core), B9, and B16 are suitable biomarkers in urine. ADB-4en-PINACA (N-[1-amino-3,3-dimethyl-1-oxobutan-2-yl]-1-[pent-4-en-1-yl]-1H-indazole-3-carboxamide) was detected in Scottish prisons in December 2020, but, unlike ADB-BUTINACA, prevalence has remained low. ADB-4en-PINACA was incubated with HHeps, and 11 metabolites were identified. Metabolites E3 (dihydrodiol formed in the tail moiety) and E7 (hydroxylation on the linked/head group) are the most abundant metabolites in vitro and are suggested as urinary biomarkers. The in vitro potencies of ADB-BUTINACA (EC50 , 11.5 nM and ADB-4en-PINACA (EC50 , 11.6 nM) are similar to that of MDMB-4en-PINACA (EC50 , 4.3 nM). A third tert-leucinamide SCRA, ADB-HEXINACA was also detected in prison samples and warrants further investigation.


Subject(s)
Cannabinoids , Prisons , Cannabinoid Receptor Agonists , Forensic Toxicology , Humans , Indazoles
4.
Forensic Sci Int ; 322: 110744, 2021 May.
Article in English | MEDLINE | ID: mdl-33721827

ABSTRACT

A method for the quantitative analysis of delta-9-tetrahydrocannabinol (THC, the main active ingredient of cannabis) in whole blood using solid phase extraction and LC/MS/MS has been developed. A bottom-up approach with method validation data was used to evaluate and estimate the measurement uncertainty (MU) of the analytical method. The sources of uncertainty were identified using a cause and effect diagram. The contribution of each uncertainty component was estimated and were combined to derive the overall uncertainty of the analytical method. The combined uncertainty was estimated to be 0.131 µg/L (<7%). At a 99.7% confidence level, the expanded uncertainty was 0.393 µg/L for a THC concentration of 2 µg/L in a whole blood sample. The calculations not only enable the laboratory to quantify the uncertainty associated with a quantitative result, but can also be used to identify the sources of uncertainty and determine if the analytical method can be improved. An open access Measurement Uncertainty Calculator (MUCalc) software has been developed using the method described in this paper.


Subject(s)
Dronabinol/blood , Models, Statistical , Chromatography, Liquid , Forensic Toxicology , Hallucinogens/blood , Humans , Mass Spectrometry , Solid Phase Extraction , Substance Abuse Detection , Uncertainty
5.
Drug Test Anal ; 13(4): 841-852, 2021 Apr.
Article in English | MEDLINE | ID: mdl-33463894

ABSTRACT

The synthetic cannabinoid receptor agonist (SCRA) market is transnational, and the availability of individual SCRAs changes regularly in response to national and international legislative controls. This generates a cyclic pattern and near constant evolution of SCRA compounds. This study reports toxicology-based and/or seized sample-based prevalence data relating to SCRA use in prisons from Germany, the United Kingdom (UK; Scotland and Wales), and the United States (US), representing 4427 individual test results. The study examines SCRA detections in prisons from July 2018 to September 2020, and where possible, prison-based data are compared with SCRA prevalence data in the wider population. The relative influence of Chinese, other international, and national drug legislation on the prevalence of individual SCRAs in prisons is also considered. tert-Leucinate- and valinate-indole- and indazole-3-carboxamides were the most common SCRA detections, and MDMB-4en-PINACA was one of the most commonly detected SCRAs in all jurisdictions by September 2020. However, despite there being a global production and supply market, there were notable regional differences. Analog controls in German and US legislation may have led to increased compound diversity that is not reflected in the UK which has both analog controls and a blanket ban on psychoactive substances. While there were regional differences, SCRA prevalence in prisons closely aligned with the SCRAs detected on the local market, demonstrating that SCRA (and possibly other NPS) monitoring programs in prisons can act as early warning systems for the wider population in that given jurisdiction.


Subject(s)
Cannabinoid Receptor Agonists/supply & distribution , Illicit Drugs/supply & distribution , Legislation, Drug , Prisons/statistics & numerical data , Germany , Humans , Illicit Drugs/legislation & jurisprudence , United Kingdom , United States
6.
Drug Test Anal ; 13(3): 644-663, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33058556

ABSTRACT

Synthetic cannabinoid receptor agonists (SCRAs), colloquially known as "spice," are commonly used in prisons and enter establishments via the mail in the form of infused papers. Many prisons use benchtop ion mobility spectroscopy (IMS) instruments to screen mail and seized materials for the presence of SCRAs and other controlled substances. The selectivity and sensitivity of Rapiscan Itemiser® 3E and Itemiser® 4DN Ion Trap Mobility Spectroscopy™ (ITMS™) systems were evaluated using 21 SCRA reference standards. Some differences in the SCRA reduced mobility (K0 ) values were observed between this study and those reported previously using IMS detection systems, particularly for cumyl and quinolinyl SCRAs (e.g., 5F-PB-22, Cumyl-4CN-BINACA, and 5F-Cumyl-PEGACLONE), although this was found to have little effect at an operational level. Operational reliability of the systems was evaluated by analyzing 392 paper and card samples with known drug content. ITMS™ system results (e.g., detect or nondetect) were in agreement with gas chromatography-mass spectrometry (GC-MS) analysis in up to 95% of samples tested. Overall, this study found the ITMS™ systems tested to be effective instruments when deployed for the rapid detection of SCRA-infused papers. Used effectively and with up-to-date substance libraries, they will help reduce the supply of SCRAs into prisons and identify emerging threats as they arise. Several emerging SCRAs (5F-MPP-PICA, 5F-EMB-PICA, and 4F-MDMB-BICA) were detected for the first time in Scottish prisons between May and August 2020 as a result of routine monitoring, and all were detected using the ITMS™ systems tested.


Subject(s)
Cannabinoid Receptor Agonists/analysis , Illicit Drugs/analysis , Ion Mobility Spectrometry/methods , Cannabinoid Receptor Agonists/chemistry , Gas Chromatography-Mass Spectrometry , Humans , Illicit Drugs/chemistry , Paper , Prisons , Reproducibility of Results , Scotland
7.
Drug Test Anal ; 13(3): 628-643, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33161649

ABSTRACT

Synthetic cannabinoid receptor agonists (SCRAs) elicit many of their psychoactive effects via type-1 human cannabinoid (CB1 ) receptors. Enantiomer pairs of eight tert-leucinate or valinate indole- and indazole-3-carboxamide SCRAs were synthesized and their CB1 potency and efficacy assessed using an in vitro ß-arrestin recruitment assay in a HEK239T stable cell system. A chiral high-performance liquid chromatography method with photodiode array and/or quadrupole time-of-flight-mass spectrometry detection (HPLC-PDA and HPLC-PDA-QToF-MS) was applied to 177 SCRA-infused paper samples seized in Scottish prisons between 2018 and 2020. In most samples, SCRAs were almost enantiopure (S)-enantiomer (>98% of total chromatographic peak area), although in some (n = 18), 2% to 16% of the (R)-enantiomer was detected. (S)-enantiomers are consistently more potent than (R)-enantiomers and often more efficacious. The importance of SCRA-CB1 receptor interactions in the "head" or "linked group" moiety is demonstrated, with the conformation of the "bulky" tert-leucinate group greatly affecting potency (by up to a factor of 374), significantly greater than the difference observed between valinate SCRA enantiomers. (S)-MDMB-4en-PINACA, (S)-4F-MDMB-BINACA, and (S)-5F-MDMB-PICA are currently the most prevalent SCRAs in Scottish prisons, and all have similar high potency (EC50 , 1-5 nM) and efficacy. Infused paper samples were compared using estimated intrinsic efficacy at the CB1 receptor (EIECB1 ) to evaluate samples with variable SCRA content. Given their similar potency and efficacy, any variation in CB1 receptor-mediated psychoactive effects are likely to derive from variation in dose, mode of use, pharmacokinetic differences, and individual factors affecting the user, rather than differences in the specific SCRA present.


Subject(s)
Cannabinoid Receptor Agonists/analysis , Chromatography, High Pressure Liquid/methods , Illicit Drugs/analysis , Mass Spectrometry/methods , Biological Assay/methods , Cannabinoid Receptor Agonists/chemical synthesis , Cannabinoid Receptor Agonists/chemistry , HEK293 Cells , Humans , Illicit Drugs/chemical synthesis , Illicit Drugs/chemistry , Paper , Prisons , Scotland , Stereoisomerism , beta-Arrestins/metabolism
8.
Forensic Toxicol ; 37(1): 1-16, 2019.
Article in English | MEDLINE | ID: mdl-30636980

ABSTRACT

PURPOSE: A detailed review on the chemistry and pharmacology of non-fentanil novel synthetic opioid receptor agonists, particularly N-substituted benzamides and acetamides (known colloquially as U-drugs) and 4-aminocyclohexanols, developed at the Upjohn Company in the 1970s and 1980s is presented. METHOD: Peer-reviewed literature, patents, professional literature, data from international early warning systems and drug user fora discussion threads have been used to track their emergence as substances of abuse. RESULTS: In terms of impact on drug markets, prevalence and harm, the most significant compound of this class to date has been U-47700 (trans-3,4-dichloro-N-[2-(dimethylamino)cyclohexyl]-N-methylbenzamide), reported by users to give short-lasting euphoric effects and a desire to re-dose. Since U-47700 was internationally controlled in 2017, a range of related compounds with similar chemical structures, adapted from the original patented compounds, have appeared on the illicit drugs market. Interest in a structurally unrelated opioid developed by the Upjohn Company and now known as BDPC/bromadol appears to be increasing and should be closely monitored. CONCLUSIONS: International early warning systems are an essential part of tracking emerging psychoactive substances and allow responsive action to be taken to facilitate the gathering of relevant data for detailed risk assessments. Pre-emptive research on the most likely compounds to emerge next, so providing drug metabolism and pharmacokinetic data to ensure that new substances are detected early in toxicological samples is recommended. As these compounds are chiral compounds and stereochemistry has a large effect on their potency, it is recommended that detection methods consider the determination of configuration.

10.
Forensic Sci Int ; 266: 202-208, 2016 Sep.
Article in English | MEDLINE | ID: mdl-27314546

ABSTRACT

A cost effective hydrogel test kit was successfully developed for the detection of pre- and post-blast trinitrotoluene (TNT). A polyvinyl alcohol (PVA) hydrogel matrix was used to entrap the potassium hydroxide (KOH) colourimetric reagent. The easily portable test kit was fabricated in situ in a small tube to which the sample could be added directly. The test kit was used in conjunction with digital image colourimetry (DIC) to demonstrate the rapid quantitative analysis of TNT in a test soil sample. The built-in digital camera of an iPhone was used to capture digital images of the colourimetric products from the test kit. Red-Green-Blue (RGB) colour data from the digital images of TNT standard solutions were used to establish a calibration graph. The validation of the DIC method indicated excellent inter day precision (0.12-3.60%RSD) and accuracy (93-108% relative accuracy). Post-blast soil samples containing TNT were analysed using the test kit and were in good agreement with spectrophotometric analysis. The intensity of the RGB data from the TNT complex deviated by +6.3%, +5.1%, and -4.9% after storage of the test kits in a freezer for 3 months. The test kit was also reusable for up to 12 times with only -5.4%, +0.3%, and +4.0% deviations. The hydrogel test kit was applied in the detection of trace explosive residues at the scene of the recent Bangkok bombing at the Ratchaprasong intersection and produced positive results for TNT demonstrating its operational field application as a rapid and cost effective quantitative tool for explosive residue analysis.

11.
Talanta ; 148: 721-8, 2016 Feb 01.
Article in English | MEDLINE | ID: mdl-26653508

ABSTRACT

It can be very challenging to recover explosives traces from porous surfaces, such as clothing and car seats, compared to non-porous surfaces. The contact heater has been developed as a novel instrument designed to recover explosives traces from porous surfaces. Samples are taken by heating and drawing air across a surface, with the air flowing through a sampling cartridge containing adsorbent polymer beads, which act to trap any recovered explosive material. Any collected explosive can then be eluted from this cartridge using a solvent, prior to analysis. This paper outlines work performed to evaluate the usefulness of the contact heater with regards to the recovery of explosives traces from porous materials. Ethylene glycol dinitrate (EGDN) and triacetone triperoxide (TATP) were chosen as two representative explosives for this study. Quantification was performed using GC-MS for EGDN and LC-MS/MS for TATP. Different sampling temperatures, sampling times and elution solvents were investigated. Recovery was trialled from leather, carpet and denim. Recoveries of up to 71% were obtained following optimisation. It was also possible to recover TATP from fabrics exposed to TATP vapour in a vapour-laden jar up to two hours after exposure. The contact heater therefore appears to be a very useful tool for the recovery of explosives traces from porous materials.


Subject(s)
Explosive Agents/analysis , Forensic Medicine/methods , Hot Temperature , Tandem Mass Spectrometry/methods , Forensic Medicine/instrumentation , Porosity , Surface Properties , Tandem Mass Spectrometry/instrumentation
12.
Sci Justice ; 55(6): 437-45, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26654079

ABSTRACT

Digital image colourimetry was successfully applied in the semi-quantitative analysis of ammonium nitrate using Griess's test with zinc reduction. A custom-built detection box was developed to enable reproducible lighting of samples, and was used with the built-in webcams of a netbook and an ultrabook for on-site detection. The webcams were used for colour imaging of chemical reaction products in the samples, while the netbook was used for on-site colour analysis. The analytical performance was compared to a commercial external webcam and a digital single-lens reflex (DSLR) camera. The relationship between Red-Green-Blue intensities and ammonium nitrate concentration was investigated. The green channel intensity (IG) was the most sensitive for the pink-violet products from ammonium nitrate that revealed a spectrometric absorption peak at 546 nm. A wide linear range (5 to 250 mgL⁻¹) with a high sensitivity was obtained with the built-in webcam of the ultrabook. A considerably lower detection limit (1.34 ± 0.05mgL⁻¹) was also obtained using the ultrabook, in comparison with the netbook (2.6 ± 0.2 mgL⁻¹), the external web cam (3.4 ± 0.1 mgL⁻¹) and the DSLR (8.0 ± 0.5 mgL⁻¹). The best inter-day precision (over 3 days) was obtained with the external webcam (0.40 to 1.34%RSD), while the netbook and the ultrabook had 0.52 to 3.62% and 1.25 to 4.99% RSDs, respectively. The relative errors were +3.6, +5.6 and -7.1%, on analysing standard ammonium nitrate solutions of known concentration using IG, for the ultrabook, the external webcam, and the netbook, respectively, while the DSLR gave -4.4% relative error. However, the IG of the pink-violet reaction product suffers from interference by soil, so that blank subtraction (|IG-IGblank| or |AG-AGblank|) is recommended for soil sample analysis. This method also gave very good accuracies of -0.11 to -5.61% for spiked soil samples and the results presented for five seized samples showed good correlations between the various imaging devices and spectrophotometer used to determine ammonium nitrate concentrations. Five post-blast soil samples were also analysed and pink-violet product were observed using Griess's test without zinc reduction indicating the absence of ammonium nitrate. This demonstrates significant potential for practical and accurate on-site semi-quantitative determinations of ammonium nitrate concentration.

13.
Sci Justice ; 54(5): 327-34, 2014 Sep.
Article in English | MEDLINE | ID: mdl-25278193

ABSTRACT

This paper considers how likelihood ratios can be derived for a combination of physical, chemical and isotopic measurements. Likelihood ratios were formulated based on the characteristics of a small convenience sample of 20 duct tapes. The propositions considered were: The physical and isotopic characteristics of ten rolls of duct tape were shown to be consistent throughout each roll. The width and thickness of the tapes and the density of the scrim fibres provided equivalent information and the combined physical characteristics provided a basis upon which to discriminate between many of the samples. Scatter-plots and confidence ellipses provided a convenient method to group the isotopic composition of the tape backing material and provided a basis to discriminate between samples which were physically indistinguishable. Considering both the physical and isotopic characteristics it was possible, at best, to ascertain that the evidence provided moderately strong support for the proposition that two samples of tape were derived from the same batch (LR=400). Kernel density estimates were used to model the distribution of isotopic compositions of the backing material. Using this technique it was possible to estimate objectively the probability that a sample with given characteristics could be drawn, at random, from the background population and to calculate a likelihood ratio based on the propositions above. The strength of evidence which could be presented by either model was ultimately limited by the size of the background sample.

14.
Sci Justice ; 53(3): 278-85, 2013 Sep.
Article in English | MEDLINE | ID: mdl-23937935

ABSTRACT

Illicit drugs manufactured from clandestine laboratories are often impure due to poor laboratory conditions, variations in synthesis and impure starting materials extracted either from common household products or pharmaceutical grade chemicals. Inductively coupled plasma mass spectrometry (ICPMS) can be utilised as a multi-element analytical tool to elicit the inorganic impurities which may be present in such samples, however the interpretation of the resultant data can be problematic and complex. This is particularly true when dealing with seized samples of unknown provenance. In this work, we have presented and interpreted inorganic profiles as a means to explore within and between batch variations in known provenance samples produced via two different popular synthetic routes. Samples were prepared from essential chemicals recovered from household materials and pharmaceutical medication available in the UK and extracted using different solvents. The presence or absence of elements in the final synthesised products could be linked to the synthesis route, salting out method and potentially the solvent used in the precursor extraction process.

15.
Sci Justice ; 53(1): 8-13, 2013 Mar.
Article in English | MEDLINE | ID: mdl-23380056

ABSTRACT

Enhancement of footwear impressions, using ninhydrin or ninhydrin analogues is not considered common practice and such techniques are generally used to target amino acids present in fingermarks where the reaction gives rise to colour and possibly fluorescence. Ninhydrin and two of its analogues were used for the enhancement of footwear impressions in blood on various types, colours and porosities of fabric. Test footwear impressions on fabric were prepared using a specifically built rig to minimise the variability between each impression. Ninhydrin enhancement of footwear impressions in blood on light coloured fabric yielded good enhancement results, however the contrast was weak or non-existent on dark coloured fabrics. Other ninhydrin analogues which have the advantage of fluorescence failed to enhance the impressions in blood on all fabrics. The sequential treatment of impressions in blood on fabric with other blood enhancing reagents (e.g. protein stains and heme reagents) was also investigated.


Subject(s)
Blood , Shoes , Staining and Labeling , Animals , Cattle , Forensic Sciences , Indans/chemistry , Indicators and Reagents , Ninhydrin/chemistry
16.
Anal Bioanal Chem ; 405(9): 2931-41, 2013 Mar.
Article in English | MEDLINE | ID: mdl-23241818

ABSTRACT

A number of methods of clandestine manufacture of methylamphetamine involve the extraction and subsequent reaction of pseudoephedrine hydrochloride with other essential chemicals. The precursor can be easily extracted from over-the-counter medication widely available in the UK and elsewhere. Essential chemicals such as iodine and red phosphorous are also readily available and can be extracted from iodine tinctures and matchboxes, respectively. This work reports the repetitive preparation of methylamphetamine using two popular routes (the Moscow and Hypophosphorous synthesis). The focus was on the extraction solvent used for isolation of the precursor chemical and any consequential isotopic variation which may arise in the final product. Six batches of methylamphetamine were prepared under precisely controlled conditions for each synthetic route and for each of three different precursor extraction solvents. Synthesis of the final product from laboratory grade precursor using the synthetic methods described was used as a template for comparison. The resultant IRMS data from all 48 prepared samples suggests some underlying trends in the identification of the synthetic route which may aid in the interpretation of IRMS data derived from clandestine samples.


Subject(s)
Central Nervous System Stimulants/chemical synthesis , Methamphetamine/chemical synthesis , Carbon Isotopes/analysis , Central Nervous System Stimulants/chemistry , Chemistry Techniques, Synthetic/methods , Deuterium/analysis , Methamphetamine/chemistry , Nitrogen Isotopes/analysis , Pseudoephedrine/chemical synthesis , Pseudoephedrine/chemistry , Solvents , Tablets
17.
Forensic Sci Int ; 223(1-3): 321-9, 2012 Nov 30.
Article in English | MEDLINE | ID: mdl-23127659

ABSTRACT

This paper focuses on the determination of route specific impurities produced when methylamphetamine is synthesised using the Birch reduction. Previous work available in the scientific literature reported only one route specific impurity using ephedrine hydrochloride as the starting material. In this paper we investigated the impurity profiles of methylamphetamine produced from both the salt and base forms of ephedrine and pseudoephedrine. A new previously unreported route specific impurity was revealed as was the potential absence of the previously reported impurity in the profile of samples prepared from the free base.

18.
Anal Chem ; 84(20): 8691-6, 2012 Oct 16.
Article in English | MEDLINE | ID: mdl-22954152

ABSTRACT

Several recent deaths in the U.K. have been attributed to "legal high" drugs and in particular to (±)-4-methylmethcathinone ((±)-mephedrone). Recent literature has begun to focus on the chemical analysis of mephedrone and related substituted cathinones and methcathinones; however, no studies involving the application of stable isotope analysis to these compounds has yet emerged. Such studies have, for example, the potential to provide information linking the final products to a particular precursor by the manufacturer. In this study, the use of stable isotope profiling was explored to provide a possible connection between product and precursor chemicals. Six samples each of mephedrone were prepared using precursor chemicals from two different manufacturers, providing 12 samples in total. Synthesis was via a stable intermediate.


Subject(s)
Illicit Drugs/chemical synthesis , Methamphetamine/analogs & derivatives , Carbon Isotopes/analysis , Chemical Fractionation , Deuterium/analysis , Illicit Drugs/chemistry , Methamphetamine/chemical synthesis , Methamphetamine/chemistry , Nitrogen/analysis , Stereoisomerism
19.
Forensic Sci Int ; 222(1-3): 340-5, 2012 Oct 10.
Article in English | MEDLINE | ID: mdl-22906588

ABSTRACT

A rapid quantitative colourimetric test was developed for the determination of 2,4,6-Trinitrotoluene (TNT) in soil. Quantification was achieved using an innovative application of photography where the relationship between the Red Green Blue (RGB) value and concentration of colorimetric product was exploited. The wide linear range (1-50 mg/L) and low detection limit (0.73±0.01 mg/L to 3.5±0.4 mg/L) achieved was comparable with spectrophotometric quantification methods. Quantification was validated both with known concentration standards and spiked soil extracts confirming the accuracy of the technique. The results demonstrate a powerful technique with the capacity for development as a rapid on site field test for the analysis of explosives.

20.
Sci Justice ; 52(3): 168-76, 2012 Sep.
Article in English | MEDLINE | ID: mdl-22841140

ABSTRACT

Footwear impression lifting and enhancement techniques may be affected by several variables introduced during the production of test footwear impressions, thus limiting the usefulness of enhancement technique comparisons and the results obtained. One such variable is the force applied when the impressed mark is being made. Producing consistent test impressions for research into footwear enhancement techniques would therefore be beneficial. This study was designed to control pressure in the production of test footwear impressions when mimicking a stamping action. Twenty-seven volunteers were asked to stamp on two different surfaces and the average stamping force was recorded. Information from the data obtained was used to design and build a mechanical device which could be calibrated to consistently deliver footwear impressions with the same force onto a receiving surface. Preliminary experiments using this device and different contaminants on the footwear sole have yielded consistent and repeatable impressions. Controlling the variable of pressure for the production of test impressions in this study demonstrated that the differences observed were visual (due to the amount of contaminant transferred and subsequent enhancement) and did not affect the replication of outer sole characteristics. This paper reports the development of the device and illustrates the quality of the impressions produced.


Subject(s)
Pressure , Shoes , Blood , Computers , Female , Fluorescence , Humans , Male , Models, Biological , Reproducibility of Results
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