Keeping pace with NPS releases: fast GC-MS screening of legal high products.

The continuous appearance of novel psychoactive substances (NPS) in legal high products presents a challenge for the routine analytical laboratory. A rapid screening method for NPS analysis using fast gas chromatography mass spectrometry (fast GC-MS) is presented. Twenty-three analytes, including 5-iodo-2-aminoindane (5-IAI), 1-(thiophen-2-yl)-2-methylaminopropane (MPA), 1-benzylpiperazine (BZP), 4-methylmethcathinone (mephedrone), 5,6-methylenedioxy-2-aminoindane (MDAI) and methoxetamine (MXE) were separated within 4 min. The method was used to analyze 35 Internet and head shop purchased 'legal high' products with the successful identification of their active ingredients. As previously observed, legal high products do not always contain their stated ingredients. Of the group of products purchased as 5-IAI not one contained 5-IAI with several containing mixtures of substances either already controlled in the UK or under consideration by the Advisory Council on Misuse of Drugs (ACMD). The low bleed and high inertness of the chromatography column used ensured clean high quality mass spectrometry data which when combined with the short run time resulted in an efficient tool for NPS screening, even when standards were unavailable. Electron impact and chemical ionization mass spectra used in combination for the identification of unknown NPS are presented.

Investigation into the suitability of capillary tubes for microcrystalline testing.

A comparison between microcrystalline tests performed on microscope slides and flat capillary tubes with inner diameters ranging from 0.1 to 0.7 mm was carried out to explore the appropriateness of tubes for rapid testing of suspected drugs of abuse in the laboratory as well as in the field. Tests for mephedrone, cocaine, and phencyclidine were chosen as examples to investigate the handling of the capillary tubes, the influence on crystal habit, size, and the effects on the limit of detection. Image stacking software was used to increase the depth of field of micrographs taken from developed microcrystals greatly enhancing the interpretability even months after carrying out the microcrystalline test. Additionally, the potential of seeding capillary tubes with a reagent was studied. Pre-treatment of tubes would allow microcrystalline tests to be carried out quicker and anywhere without the necessity of taking along expensive and hazardous reagents. The sealing of capillary tubes containing developed microcrystalline tests in order to preserve results for a long period of time was successfully done by applying paraffin wax to the open ends. Finally, it was concluded that capillary tubes are suitable vessels for performing microcrystalline tests. The increased portability of the improved set-up allows tests to be safely executed outside laboratories without impairing the quality of the result. Findings were applied to six legal high samples purchased online between May and August 2011. The active ingredients like MDAI as well as cutting agents like caffeine were successfully identified using the microcrystalline test technique in capillary tubes.

Injection port silylation of γ-hydroxybutyrate and trans-hydroxycrotonic acid: conditions optimisation and characterisation of the di-tert-butyldimethylsilyl derivatives by GC-MS.

Silylation is usually carried out on γ-hydroxybutyrate (GHB) for its analysis by Gas Chromatography/Mass Spectrometry (GCMS) and requires potentially long incubation times before injection during which the derivatisation reagent and derivatives (such as trimethyl-silyl compounds) can hydrolyse. Moreover, alternative internal standards (IS) are often useful depending on sample matrices, extraction/purification procedures, commercial availability and price. This study evaluated the possibility of silylating GHB with an injection port derivatisation procedure using N-methyl-N-[tert-butyldimethyl-silyl]trifluoroacetimide (MTBSTFA) with 1% tert-butyldimethylchlorosilane (TBCS) as the derivatisation reagent, producing di-tert-butyldimethyl-silyl derivatives as a novel means of analyzing GHB. In parallel, trans-hydroxycrotonic acid (t-HCA) was investigated as a potential IS for GHB quantification. Analyses were carried out with a temperature programmable injector and the GHB(t-BDMS)(2) and t-HCA(t-BDMS)(2) derivatives were successfully produced, characterised and derivatisation conditions optimised. t-HCA behaved very similarly to GHB through the derivatisation processes and was used as the IS for the determination of urinary endogenous GHB concentrations in human subjects where the method showed a limit of detection of 0.049 µg mL(-1), a limit of quantification of 0.162 µg mL(-1), and a limit of confirmation of 1.33 µg mL(-1), suitable for toxicological GHB concentration determination.

Reversing microcrystalline tests--an analytical approach to recycling of microcrystals from drugs of abuse.

A combined analysis of microcrystalline tests followed by LC-MS or GC-MS analysis is described. Microcrystalline tests are shown to be non-destructive as addition products formed were easily dissociated after the application of an appropriate solvent. Subsequent analysis of the sample was done to quantify the recovery of the drug. Examples were performed using the date rape drug γ-hydroxybutyrate (GHB) and the synthetic opioid methadone.

Variation in amino acid and lipid composition of latent fingerprints.

The enhancement of latent fingerprints, both at the crime scene and in the laboratory using an array of chemical, physical and optical techniques, permits their use for identification. Despite the plethora of techniques available, there are occasions when latent fingerprints are not successfully enhanced. An understanding of latent fingerprint chemistry and behaviour will aid the improvement of current techniques and the development of novel ones. In this study the amino acid and fatty acid content of 'real' latent fingerprints collected on a non-porous surface was analysed by gas chromatography-mass spectrometry. Squalene was also quantified in addition. Hexadecanoic acid, octadecanoic acid and cis-9-octadecenoic acid were the most abundant fatty acids in all samples. There was, however, wide variation in the relative amounts of each fatty acid in each sample. It was clearly demonstrated that touching sebum-rich areas of the face immediately prior to fingerprint deposition resulted in a significant increase in the amount of fatty acids and squalene deposited in the resulting 'groomed' fingerprints. Serine was the most abundant amino acid identified followed by glycine, alanine and aspartic acid. The significant quantitative differences between the 'natural' and 'groomed' fingerprint samples seen for fatty acids were not observed in the case of the amino acids. This study demonstrates the variation in latent fingerprint composition between individuals and the impact of the sampling protocol on the quantitative analysis of fingerprints.

Enhancement of microcrystalline identification of gamma-hydroxybutyrate.

An enhancement of the microcrystalline test for the detection of gamma-hydroxybutyrate (GHB) is described. The original test used a silver/copper reagent which consisted of 0.1 g of silver nitrate and 0.1 g of copper nitrate in 10 mL water. The enhanced test utilizes lanthanum nitrate in place of copper nitrate. A detection limit of 0.5 mg/mL was achieved and the visual discrimination was improved because of larger sized crystals. Transient crystals were observed between 0.1 and 0.4 mg/mL. Silver nitrate alone appeared to be suitable for GHB detection but was not specific as other hydroxyl acids, such as glycolic acid, produced a similar crystal pattern. Tests conducted on chemical precursors of GHB and substances with similar biological activity highlight the specificity of the enhanced test. The reagent is therefore selective and sensitive for GHB in aqueous solutions. However, in beverage testing, crystal formation appeared to be inhibited for some drinks. Citric acid was identified as a possible interference depending on its concentration relative to GHB.

Review of analytical techniques for arson residues.

Arson is a serious crime that affects society through cost, property damage, and loss of life. It is important that the methods and technologies applied by fire investigators in detection of evidence and subsequent analyses have a high degree of reliability, sensitivity, and be subject to rigorous quality control and assurance. There have been considerable advances in the field of arson investigation since the 1950s. Classification of ignitable liquids has been updated to include many new categories due to developments in the petroleum industry. Techniques such as steam or vacuum distillation and gas chromatography (GC) with flame ionization detection that may have been considered acceptable--even a benchmark--40 years ago, are nowadays generally disfavored, to the extent that their implementation may almost be considered as ignorance in the field. The advent of readily available mass spectrometric techniques has revolutionized the field of fire debris analysis, increasing the degree of sensitivity and discrimination possible considerably. Multi-dimensional GC--particularly GC x GC--while not yet widely applied, is rapidly gaining recognition as an important technique. This comprehensive review focuses on techniques and practices used in fire investigation, from scene investigation to analysis.

Development of a GC-MS method for the simultaneous analysis of latent fingerprint components.

Latent fingerprint residue is a complex mixture of organic and inorganic compounds. A full understanding of the composition of this mixture and how it changes after deposition is lacking. Three solvent systems were compared for the simultaneous extraction and derivatization with ethyl chloroformate of selected amino and fatty acids from a nonporous substrate (Mylar for subsequent analysis by gas chromatography-mass spectrometry. A solvent system comprised of sodium hydroxide, ethanol, and pyridine was found to be the most effective. This method was applied to the analysis of latent fingerprint residue deposited on Mylar and preliminary data are presented. Twelve amino acids (e.g., serine, glycine, and aspartic acid) and 10 fatty acids (e.g., tetradecanoic, hexadecanoic, and octadecanoic acids) were identified. The potential application of this method to further the understanding of latent fingerprint chemistry has been demonstrated.