Vanadio determinacion

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Talanta 71 (2007) 486–492

Simultaneous determination of aliphatic and aromatic amines in indoor and outdoor air samples by gas chromatography–mass spectrometry
Mehmet Aky¨ z ∗ u
Zonguldak Karaelmas University, Faculty of Sciences and Letters, Department of Chemistry, 67100 Zonguldak, Turkey Received 15 June 2006; received in revised form 18 October 2006; accepted 19 October 2006 Availableonline 27 November 2006

Abstract A gas chromatography–mass spectrometry (GC–MS) method has been proposed for the simultaneous determination of aliphatic and aromatic amines in indoor and outdoor air samples. The method includes pre-concentration of the compounds by percolating the air samples through the acidic solution, ion-pair extraction with bis-2-ethylhexylphosphate (BEHPA), derivatisationof compounds with isobutyl chloroformate (IBCF) and their GC–MS analysis. Aliphatic and aromatic amines were isolated from aqueous samples using BEHPA as ion-pair reagent and derivatised with IBCF for their chromatographic analysis. Aliphatic and aromatic amines were then analysed with GC–MS in both electron impact (EI) and positive and negative ion chemical ionisation (PNICI) mode as theirisobutyloxycarbonyl (isoBOC) derivatives. The obtained recoveries ranged from 75.6 to 96.8% and the precision of this method, as indicated by the relative standard deviations (R.S.D.) was within the range of 1.0–4.4%. The detection limits obtained from calculations by using GC–MS results based on S/N: 3 were within the range of 0.08–0.01 ng/m3 . © 2006 Elsevier B.V. All rights reserved.
Keywords:Ion-pair extraction; Aliphatic and aromatic amines; GC–MS; Indoor–outdoor air samples

1. Introduction Volatile aliphatic amines like methylamine, dimethylamine, ethylamine, diethylamine, propylamine, dipropylamine, butylamine and dibutylamine are important air pollutants due to their odorous and toxic characteristics and they are found in the air as a result of their industrial commercialapplications or their widespread use as intermediates in chemical and pharmaceutical industries [1,2]. In addition to their toxic characteristics most of alkylamines are sensitizers and irritants to the skin, mucous membrane and respiratory tract and it is well known that they can react with nitrite, forming carcinogenic nitrosamines [3,4]. Aromatic amines like morpholine, aniline, phenylethylamine,chloroanilines, piperazine, naphthylamines, aminophenols, toluenediamines and 4-aminobiphenyl are biologically active compounds, well known as environmental pollutants because of their toxicity and carcinogenicity as they are widely used in industry to make dyes, cosmetics, medicines, rubber,



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textiles,agrochemicals and as reagents intermediates in many chemical syntheses [5,6]. Therefore, the monitoring of levels of aliphatic and aromatic amines in indoor and outdoor air is important to protect human health and the environment because of human exposure to these compounds through diet and inhalation. The most widely used techniques for the determination of aliphatic [1,2] and/or aromatic amines[5,6] in air samples are gas chromatography (GC) coupled with different detectors [1,3,5], high-performance liquid chromatography (HPLC) [4,7–10], ion chromatography [11], spectrophotometry [12]. Gas chromatography–mass spectrometry (GC–MS) has been recognized as the method of choice for the analysis of aliphatic and aromatic amines in environmental samples, due to its superiority in selectivityand sensitivity. A pre-concentration step is necessary to obtain good sensitivity and derivatisation step is generally required to improve the gas chromatographic properties because of the polarity of the amines. Liquid–liquid extraction after percolation of the air sample through the acidic solution (LLE) [6,13] and solid-phase extraction (SPE) [1,2,7,12,14] have been widely employed for the...
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