Surface-assisted laser desorption ionization mass spectrometry techniques for application in forensics.

Matrix-assisted laser desorption ionization (MALDI) mass spectrometry (MS) is an excellent analytical technique for the rapid and sensitive analysis of macromolecules (>700 Da), such as peptides, proteins, nucleic acids, and synthetic polymers. However, the detection of smaller organic molecules with masses below 700 Da using MALDI-MS is challenging due to the appearance of matrix adducts and matrix fragment peaks in the same spectral range. Recently, nanostructured substrates have been developed that facilitate matrix-free laser desorption ionization (LDI), contributing to an emerging analytical paradigm referred to as surface-assisted laser desorption ionization (SALDI) MS. Since SALDI enables the detection of small organic molecules, it is rapidly growing in popularity, including in the field of forensics. At the same time, SALDI also holds significant potential as a high throughput analytical tool in roadside, work place and athlete drug testing. In this review, we discuss recent advances in SALDI techniques such as desorption ionization on porous silicon (DIOS), nano-initiator mass spectrometry (NIMS) and nano assisted laser desorption ionization (NALDI™) and compare their strengths and weaknesses with particular focus on forensic applications. These include the detection of illicit drug molecules and their metabolites in biological matrices and small molecule detection from forensic samples including banknotes and fingerprints. Finally, the review highlights recent advances in mass spectrometry imaging (MSI) using SALDI techniques.

Detailed investigations into the Akabori-Momotani reaction for the synthesis of amphetamine type stimulants: Part 2.

The Akabori-Momotani reaction can be used to synthesise pseudoephedrine in 50% yield from N-methylalanine and benzaldehyde. This paper investigates electronic effects of substituted benzaldehydes on the reaction to synthesise amphetamine type stimulants and identifies several new Akabori-Momotani by-products, 1-[(4-methoxybenzyl)(methyl)amino]ethanol (11c), 2-(4-methoxyphenyl)-3,4-dimethyl-1,3-oxazolidine (12c), 1,2,3,4-tetramethyl-5,6-di-(4-methoxyphenyl)piperazine (13c) and 1,2,4,5-tetramethyl-3,6-di-(4-methoxyphenyl)piperazine (14c). This paper also investigates pseudoephedrine and methamphetamine isomeric distribution from the Akabori-Momotani reaction with the aid of molecular modelling to understand why more pseudoephedrine than ephedrine is produced.

The synthesis and investigation of impurities found in Clandestine Laboratories: Baeyer-Villiger Route Part I; Synthesis of P2P from benzaldehyde and methyl ethyl ketone.

The synthesis of impurities detected in clandestinely manufactured Amphetamine Type Stimulants (ATS) has emerged as more desirable than simple "fingerprint" profiling. We have been investigating the impurities formed when phenyl-2-propanone (P2P) 5, a key ATS precursor, is synthesised in three steps; an aldol condensation of benzaldehyde and methyl ethyl ketone (MEK); a Baeyer-Villiger reaction; and ester hydrolysis. We have identified and selectively synthesised several impurities that may be used as route specific markers for this series of synthetic steps. Specifically these impurities are 3-methyl-4-phenyl-3-buten-2-one 3, 2-methyl-1,5-diphenylpenta-1,4-diene-3-one 9, 2-(methylamino)-3-methyl-4-phenyl-3-butene 16, 2-(Methylamino)-3-methyl-4-phenylbutane 17, and 1-(methylamino)-2-methyl-1,5-diphenylpenta-4-ene-3-one 22.

Clandestine drug laboratories in Australia and the potential for harm.

The emphasis in the literature regarding illicit drugs has been overwhelmingly on the subject of harm caused by their ingestion. Little has been reported on the potential and real harm associated with the illicit manufacture of drugs. This paper describes the increasing prevalence of clandestine drug laboratories in Australia, overwhelmingly devoted to the manufacture of methamphetamine. The nature of the illicit synthetic process is reviewed together with its inherent dangers for the 'cook', first responders and bystanders including children, and the environment. We have analysed the emerging trends in manufacture and seizure in Australia, and offer suggestions to remedy significant deficiencies in knowledge and policy in the management of clandestine drug laboratories, especially with reference to clinical management issues, data collection, environmental contaminants and remediation, legislation and research. In particular, we conclude that: The problem of clandestine drug laboratories is growing in Australia, reflecting patterns world-wide. There are significant health and environmental implications of this growth. First responders should ensure that specialised expertise is available when decommissioning detected laboratories. Clinicians should familiarise themselves with the types of injuries associated with clandestine drug manufacture. Legislatures without a clandestine drug laboratory registry should establish one. Where it doesn't exist, legislation should be sought to curb the spread of this unwanted phenomenon. Significant opportunities exist for further research into the harm caused to first responders, the community, and the environment by clandestine laboratories.

New developments in SPME, Part 1: The use of vapor-phase deprotonation and on-fiber derivatization with alkylchloroformates in the analysis of preparations containing amphetamines.

Due to their high polarity and low vapor pressure, most amine salts of amphetamine-type drugs are not directly amenable to headspace recovery using solid-phase microextraction (SPME). Described in this article is a simple vapor-phase procedure for the conversion of solid drug salt samples into their free bases by the use of triethylamine. This process can be conducted simultaneously with headspace SPME, the outcome being that solid drug salts can be sampled directly for GC-MS without the need for dissolution and chemical processing. Potential applications for this methodology include the noninvasive recovery of drug traces from objects such as banknotes and garments. This new process for recovery of amphetamine-type drugs has been combined with on-fiber derivatization using alkylchloroformates. This extra step was included to improve the chromatographic performance of analytes and allow for the resolution of drug enantiomers.

New developments in SPME Part 2: Analysis of ammonium nitrate-based explosives.

Solid-phase microextraction (SPME) followed by gas chromatography-mass spectrometry (GC-MS) is a simple, reliable technique for the recovery and analysis of many organic explosives. However, this technique is impractical for the analysis of ammonium nitrate-type explosives due to the extreme polarity, low molecular weight, and high volatility of the amine moiety. This article describes an initial investigation of a derivatization process utilizing alkylchloroformates that converts ammonium nitrate and methylammonium nitrate into a form suitable for recovery by SPME and analysis by GC-MS.

Evaluation of some oxygen, sulfur, and selenium substituted ninhydrin analogues, nitrophenylninhydrin and benzo[f]furoninhydrin.

Six ninhydrin analogues containing oxygen, sulfur, and selenium substituents at the C-5 position, 5-(4-nitrophenyl)ninhydrin, and benzo[f]furoninhydrin were evaluated as fingerprint development reagents. The analogues all showed good fingerprint color development but were not superior to ninhydrin in this respect. The benzo[f]furoninhydrin complex was strongly luminescent at room temperature following zinc complexation, while the remaining analogues required cooling to -196 degrees C to produce optimum luminescence. The benzo[f]furo, nitrophenyl, and methyl selenide analogues showed the best potential as fingerprint reagents with the benzo[f]furo analogue comparing favorably with DFO.