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Ehleringer J.R.,University of Utah | Ehleringer J.R.,SALt Inc | Casale J.F.,Special Testing and Research Laboratory | Barnette J.E.,University of Utah | And 5 more authors.
Forensic Science International | Year: 2012

Measurements were made on the natural abundance 14C content (Δ 14C) of cocaine specimens seized between 2003 and 2009. The objective of this study was to determine the extent to which Δ 14C analyses could quantify the "age" of recent cocaine seizures. Here "age" of a seized cocaine specimen is defined as the time period between when a coca leaf was harvested in South America and its seizure as cocaine at either the international or domestic street levels. Based on Δ 14C analyses of seizure specimens, there were no statistically significant differences in the ages of domestic cocaine HCl and cocaine base specimens seized on the streets in different locations across the United States. Between 2007 and 2009, the average age of a street-level cocaine seizure in the United States was 24.6±1.1months. Cocaine shipment seizures that were in excess of 150kg during this time period had an average age of 18.2±1.4months, whereas smaller shipment seizures were significantly older with an average age of 22.3±0.6months. Analyses of the largest cocaine shipment seizures suggested that these seizures were composed of specimens with different ages, possibly representing accumulations over as much as a 31-month period. © 2011 Elsevier Ireland Ltd.

Li L.,Special Testing and Research Laboratory | Lurie I.S.,George Washington University
Forensic Science International | Year: 2014

The use of psychoactive "designer drugs" has increased rapidly due to their varying and sometimes ambiguous legal status and their ready access via the Internet and at local "headshops." A quick screening method for samples containing these substances, using ultra-high performance liquid chromatography with photodiode array UV and mass spectrometric detection (UHPLC-PDA/UV-MS), is presented. The method enables the screening of a variety of samples containing emerging/reemerging drugs, including β-keto phenethylamines (cathinone derivatives), synthetic cannabinoids/cannabimimetics, and phenethylamine derivatives. The use of dual detectors not only provides molecular weight information but also differentiates the drugs by their categories and in some cases even their sub-categories. Moreover, ring positional isomers of cathinone and phenethylamine derivatives can be easily differentiated by their retention times and UV spectra. © 2014.

Li L.,Special Testing and Research Laboratory | Lurie I.S.,Special Testing and Research Laboratory | Lurie I.S.,George Washington University
Forensic Science International | Year: 2015

Designer: phenethylamines (PEAs) and cathinones have been encountered worldwide. Complete characterization of these substances can be challenging due to their chirality and variably substituted phenyl rings. In this study, 24 PEAs and cathinones were analyzed by ultra high performance liquid chromatography with photo diode array detection (UHPLC-PDA) on a variety of stationary phases, and by capillary electrophoresis on a dynamically coated capillary with PDA detection (CE-PDA). In the UHPLC-PDA study, a BEH Phenyl column resolved 18 of the 24 regioisomers in 8. min, with good discrimination of the PEAs. In contrast, capillary zone electrophoresis (CZE) on a dynamically coated capillary partially or baseline resolved only 10 of the 24 regioisomers, but with improved discrimination of mono-substituted cathinones. A second series of CE-PDA experiments using 80. mM (2-hydroxypropyl)-β-cyclodextrin (HP-β-CD) in the run buffer resolved all 24 regioisomers and all but two sets of enantiomers within 18. min. Five illicit samples were successfully analyzed using the described methods. © 2015 Published by Elsevier Ireland Ltd.

Mallette J.R.,Special Testing and Research Laboratory | Casale J.F.,Special Testing and Research Laboratory
Journal of Chromatography A | Year: 2014

The isomeric truxillines are a group of minor alkaloids present in all illicit cocaine samples. The relative amount of truxillines in cocaine is indicative of the variety of coca used for cocaine processing, and thus, is useful in source determination. Previously, the determination of isomeric truxillines in cocaine was performed with a gas chromatography/electron capture detection method. However, due to the tedious sample preparation as well as the expense and maintenance required of electron capture detectors, the protocol was converted to a gas chromatography/flame-ionization detection method. Ten truxilline isomers (alpha-, beta-, delta-, epsilon-, gamma-, omega, zeta-, peri-, neo-, and epi-) were quantified relative to a structurally related internal standard, 4',4″-dimethyl-α-truxillic acid dimethyl ester. The method was shown to have a linear response from 0.001 to 1.00. mg/mL and a lower detection limit of 0.001. mg/mL. In this method, the truxillines are directly reduced with lithium aluminum hydride and then acylated with heptafluorobutyric anhydride prior to analysis. The analysis of more than 100 cocaine hydrochloride samples is presented and compared to data obtained by the previous methodology. Authentic cocaine samples obtained from the source countries of Colombia, Bolivia, and Peru were also analyzed, and comparative data on more than 23,000 samples analyzed over the past 10 years with the previous methodology is presented. © 2014.

Mallette J.R.,Special Testing and Research Laboratory | Casale J.F.,Special Testing and Research Laboratory
Journal of Forensic Sciences | Year: 2015

This study presents data that establish the makeup of solvents utilized in illicit cocaine hydrochloride production, as determined via the identification of the occluded solvents in the crystal matrix of the final product. The occluded solvent ratios can differ dramatically from the ratios of the original processing solvents. Additionally, the presented data suggest the diversion of commercial solvents to illicit cocaine hydrochloride laboratories. Thirty-five commercial solvents were obtained from five chemical manufacturing companies in South America. Each solvent was qualitatively and quantitatively analyzed using static headspace-gas chromatography-mass spectrometry (HS-GC-MS). After obtaining the chemical profile for each commercial solvent, solvents and/or solvent mixtures were prepared to be comparable in composition to several of the commercial products. Over 90 individual batches of cocaine hydrochloride were prepared from cocaine base using these solvents or solvent mixtures, which match those most commonly employed in clandestine laboratories. Additionally, a number of unique manufacturing by-products produced from processing solvents were identified, and their significance is discussed. © 2014 American Academy of Forensic Sciences.

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