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

Brown, Hayley; Kirkbride, K. Paul; Pigou, Paul E.; Walker, G. Stewart

doi:10.1520/jfs2003117

Cited by 9 publications

(3 citation statements)

References 13 publications

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“…After conversion of amphetamines to their free base using triethylamine, an SPME fiber coated with an alkylchloroformate was used to sample the headspace and cause derivatization. (16) More conventionally, alkylchloroformate derivatization of cocaine and two derivatives was done before SPME and GC/MS analysis. (17) Detection limits in human hair of 0.1-0.5 ng mg −1 were similar to those reported in reference 16.…”

Section: Alkylationmentioning

confidence: 99%

Chemical Reagents and Derivatization Procedures in Drug Analysis

Danielson

Gallagher

Bao

2008

Encyclopedia of Analytical Chemistry

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This article describes both pre‐ and postcolumn derivatization chemistry used in conjunction with either chromatography or capillary electrophoresis (CE) to facilitate the determination of drugs. Generally, only prederivatization is used in gas chromatography (GC), principally to enhance the volatility, temperature stability, and/or detectability. The GC section considers derivatization of drugs by reagent class: alkylation, acylation, and silylation. The GC sample‐handling section describes an approach that combines the extraction and derivatization steps together. Both pre‐ and postcolumn derivatization are common approaches for high‐performance liquid chromatography (HPLC) and many of these methods have been adapted for CE. Derivatization for HPLC is often directed toward aliphatic amines, carboxylic acids, or alcohols that are difficult to detect at low levels by absorbance, luminescence, or electrochemical means. In addition, small hydrophilic molecules upon prederivatization are often converted into larger more hydrophobic compounds, making reversed‐phase HPLC easier or even feasible. The HPLC section considers derivatization of drugs based on the following types: alkaloids, amines, antibiotics, barbiturates, carbonyl compounds and carboxylic acids, catecholamines, hydroxy compounds, steroids, and sulfur compounds. For the GC and HPLC sections, tables are included, giving the structures of the more important derivatizing agents, the analytes, and the corresponding reaction products. A brief rationale for derivatization chemistry with CE concludes this article. For CE, derivatization is often done to improve detectability as the path length for absorbance detection is very short and fluorescence can be effective using laser‐based systems.

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Section: Alkylationmentioning

confidence: 99%

Chemical Reagents and Derivatization Procedures in Drug Analysis

Danielson

Gallagher

Bao

2008

Encyclopedia of Analytical Chemistry

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“…Solid phase microextraction (SPME) has been used to trap methamphetamines from the air for subsequent analysis by GC-MS. Volatilisation, trapping and analysis of methamphetamine hydrochloride as methamphetamine free base with on-fibre derivatisation by a range of chloroformates on a range of SPME fibres have been shown to be effective in recovering methamphetamine (and precursors and by-products) from the headspace of gloves and money recovered from a clandestine laboratory [18]. Levels between 0.2 and 3 µg/m 3 have been reported in properties suspected to have been formerly used to manufacture methamphetamine in New Zealand, only where surface methamphetamine contamination exceeded 40 µg/100 cm 2 [19].…”

Section: Introductionmentioning

confidence: 99%

Current practices underestimate environmental exposures to methamphetamine: inhalation exposures are important

Wright

Symons²,

Angell³

et al. 2020

J Expo Sci Environ Epidemiol

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Current practice for determining the exposure to methamphetamine in contaminated homes relies on the analysis of surface wipe sample to address direct contact exposures. The movement of methamphetamine into the air phase, and the potential for inhalation exposures to occur within residential homes contaminated from former clandestine manufacture or smoking of methamphetamine has been generally poorly characterised and understood. All available risk-based guidelines for determining safe levels of methamphetamine in residential properties do not include any consideration of the inhalation pathway as an exposure route. This study showed that methamphetamine can readily move from contaminated materials in a home into the air phase. This movement of methamphetamine into the air phase provides both an exposure pathway and a mechanism for the transfer of methamphetamine throughout a property. The inhalation exposure pathway has the potential to result in significant intake of methamphetamine, adding to dermal absorption and ingestion exposure routes. Guidelines that are established for the assessment of methamphetamine contaminated properties that ignore inhalation exposures can significantly underestimate exposure and result in guidelines that are not adequately protective of health. This study also demonstrates that sampling methamphetamine in air can be undertaken using commercially available sorption tubes and analytical methods.

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“…It is usually performed by using acyl halides or anhydrides of halogenated acids. 13 These compounds, in particular fluoroacyl, are very reactive and improve the sensitivity and resolution of the analyses, 14 specially when the separation of enantiomers is required. 15 However, the costs of these reagents are still high for many laboratories, including the ones located in Latin America.…”

Section: Introductionmentioning

confidence: 99%

Simultaneous quantification of amphetamines and ephedrines in urine by GC/MS using analytical-grade acetic anhydride/pyridine as derivatizing reagents: a suitable approach to reduce costs of routine analyses

Bergo¹,

Correa²,

Nagem³

et al. 2009

J. Braz. Chem. Soc.

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Neste trabalho foi desenvolvido e validado um método quantitativo para a análise de anfetaminas e efedrinas em urina, utilizando-se anidrido acético e piridina, ambos em grau analítico, como derivatizantes. As amostras foram extraídas por extração em fase sólida (EFS), derivatizadas e em seguida analisadas por CG-EM. O método apresentou ampla faixa linear (25-1000 ng mL-1 com R 2 > 0,99), alta sensibilidade (LODs variando de 0,0140 a 15,33 ng mL-1 e LOQs variando de 0,0466 a 51,10 ng mL-1), bons índices de precisão (CV < 6% para intra-e inter-ensaios) e excelentes índices de recuperação (87-96%) para todos os compostos estudados. Após a validação, o método foi aplicado em análises de amostras reais de urina humana nas quais ao menos um dos analitos em estudo foi identificado previamente. Em todas as amostras, anfetaminas e efedrinas foram facilmente quantificadas mostrando que a associação de anidrido acético e piridina é uma boa opção como agente derivatizante. A GC/MS method for the simultaneous analyses of different amphetamines and ephedrines in urine employing analytical-grade acetic anhydride/pyridine as derivatizing reagents was developed and validated. Solid-phase extraction was performed on the samples, which were then derivatizated and analyzed by GC/MS. The method showed a broad linear dynamic range (25-1000 ng mL-1 with R 2 > 0.99), high sensitivity (LODs of 0.0140 to 15.33 ng mL-1 and LOQs of 0.0466 to 51.10 ng mL-1), good precision (CV < 6% for intra-and inter-assays), and excellent extraction recovery (87 to 96%) for all the compounds studied. After validation, the method was applied in the analyses of real samples of human urine which were previously determined to contain at least one of such drugs. In all the samples, the amphetamines and ephedrines were promptly quantified, showing that the association of acetic anhydride and pyridine can be conveniently employed as a derivatizing agent.

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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

Cited by 9 publications

References 13 publications

Chemical Reagents and Derivatization Procedures in Drug Analysis

Chemical Reagents and Derivatization Procedures in Drug Analysis

Current practices underestimate environmental exposures to methamphetamine: inhalation exposures are important

Simultaneous quantification of amphetamines and ephedrines in urine by GC/MS using analytical-grade acetic anhydride/pyridine as derivatizing reagents: a suitable approach to reduce costs of routine analyses

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