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The possibility of direct liquid injection inside an ion trap, designed for a commercial gas chromatography/mass spectrometry (GC/MS) system, has been tested by continuous solution flow and by loop injection. Instrumental parameters such as solution flows and sample concentration, and temperatures of transfer line, ion trap and ion trap housing, have been optimised. Different configurations of the interface capillary have been also considered, and the best results have been obtained by the injection of the solution coaxially with a helium flow. The experimental arrangement leads to the detection of good quality electron (EI) and chemical (CI) ionisation spectra of low to medium polarity compounds, at µM levels. The direct coupling of a nano-HPLC column with the modified transfer line led on one hand to EI spectra which were successfully employed for library searches, and on the other to CI data directly comparable to results achieved by a commercial HPLC/MS system operating under ESI conditions. Copyright © 2001 John Wiley & Sons, Ltd.

A new method to detect the use of banned azo dyes in the manufacture and treatment of coloured textiles and leather is described. The determination of the azo dyes was made by quantification of aromatic amines generated by reductive cleavage in a citrate buffer medium. The aromatic amines were then extracted from 1 mL of the reaction solution by means of solid phase microextraction (SPME) and determined by gas chromatography/mass spectrometry (GC/MS). We also evaluate accuracy, precision, range of linearity and limit of detection for the eighteen aromatic amines investigated, and show that the method is comparable with current established methods. Copyright © 1999 John Wiley & Sons, Ltd.

A recently developed solvent-free sampling method, solid-phase microextraction, has been employed for sampling the cuticular hydrocarbons from three species of social wasps for GM/MS analysis. Comparison between the gas chromatograms of cuticular hydrocarbons obtained by microextraction and those of hexane-extracted samples from the same specimens shows that solid-phase microextraction is very suitable for sampling insect cuticle hydrocarbons, including those of high molecular weight. Because of its simplicity, this method is very suitable for routine work. © 1997 John Wiley & Sons, Ltd.

A sensitive and accurate method to quantitate 17 primary aromatic amines in tobacco smoke has been set up. two Italian commercial brands of cigarette were smoked in a home-made smoking machine; the amines in the smoke were trapped in dilute hudrochloric acid (containing 2H5-aniline, 13C1-o-toluidine and 2H9-4-aminobiphenyl as internal standards) and, after extraction and purification, derivatized as pentafluoropro-pionamides and measured by gas chromatography/mass spectrometry in the selected-ion-monitoring mode. Our results confirmed that side-stream smoke contains total levels of aromatic amines about 50–60 times higher than those of main-stream smoke of black-tobacco cigarettes is richer in aromatic amines compared to light-tobacco cigarettes.