Development of a LC-MS/MS method for the analysis of volatile primary and secondary amines as NIT (naphthylisothiocyanate) derivatives

Abstract

High-performance liquid chromatography with mass spectrometric detection was used for the structure elucidation of eighteen primary and secondary amines and ammonia derivatised with naphthylisothiocyanate (NIT). A fragmentation scheme was established using reference compounds and the scheme was applied to real air samples from a tyre repair shop and from the air above a bacterial culture. The sampling was performed using a solid sorbent, XAD-2, impregnated with NIT, and the derivatives were extracted with acetonitrile and analysed with LC-MS/MS. A three-step process was developed for screening and identifying of volatile amines. The first step, selected reaction monitoring; SRM was applied in order to screen the samples for NIT derivatives. In the second step, a precursor ion scan gave the [M+H](+) ion, and in the third step a product ion scan gave the fragments needed for identification. The detection limits varied between 0.12 and 0.25 ng microL(-1) when screening for unknown derivatised amines. It was possible to separate and identify all the amines with the structural information obtained and the method proved to be general, sensitive and well suited for sampling and analysis of complex environmental samples.

Identification using versatile sampling and analytical methods of volatile compounds from Streptomyces albidoflavus grown on four humid building materials and one synthetic medium

“…The XAD‐2 samplers impregnated with NIT for sampling of primary and secondary amines were analyzed with HPLC‐MS‐MS (Claeson et al., 2004) with a detection limit of 0.2 ng/ μ l. The chromatographic separation was performed with a Grom‐sil 80 ODS‐7, 4 μ m 200 × 3 mm column (Grom analytic + HPLC GmbH, Herrenberg, Germany). The data were recorded and processed by the API 2000 computer system MassChrome v 1.1 (PE Sciex Instruments, Foster City, CA, USA).…”

Sensitivity enhancement in liquid chromatography/atmospheric pressure ionization mass spectrometry using derivatization and mobile phase additives

“…Difficulties in establishing an analytical method for volatile amines include their high volatility, polarity, basic character and high water solubility [45]. Problems associated with matrix effects and high background noise also exist for amines.…”

Isothiocyanates as derivatization reagents for amines in liquid chromatography/electrospray ionization–tandem mass spectrometry

“…The isothoicyanate group reacts with amines and produces thiourea structure. It is presumed that thiourea structure effi ciently produces a particular fragment ion by CID (Claeson et al, 2004;Ji and Morris, 2003). We adopted Py-NCS, DMAP-NCS and NP-NCS as the derivatization reagents for LC/ESI-MS/MS, since these reagents have the chargeable and aromatic (hydrophobic) moieties.…”