A novel sampler for aliphatic amines and a new method for determination using hydrophilic interaction liquid chromatography tandem mass spectrometry
(English)Manuscript (preprint) (Other academic)
A novel sampler for determination of airborne aliphatic amines is presented using hydrophilic interaction liquid chromatography (HILIC) with tandem mass spectrometry (MSMS). The sampler consisted of a denuder comprising a polypropylene tube (length = 7 cm, ID = 0.8 cm) with an inner wall coated with a glass fibre filter and internal glass fibre filter strip folded into a ‘V’ to increase the denuder surface coupled in series with a 13 mm glass fibre filter. Sulphuric acid was used for impregnation of all the filters.
Electrospray ionisation and multiple-reaction monitoring (MRM) of the protonated molecular ions and corresponding deuterium-labelled internal standards resulted in selective determination with linear correlation coefficients > 0.995, instrumental precision (n = 16) < 6 % and detection limits of 1.9 - 150 pg (2.6 - 195 ng mL-1) for ethylamine (EA), allylamine (AA), isopropanol amine (IPA), n-butylamine (NBA), diethylamine (DEA), dimethylethylamine (DMEA), cyclohexylamine (CHA), diisopropylamine (DIPA) and triethylamine (TEA).
The performance of the sampler was investigated by sampling a standard atmosphere of AA, IPA, NBA, DEA, DMEA, CHA and TEA (0.5-15.4 mg m-3) in an exposure chamber (0.3 m3). The air concentrations of the amines were generated by gas phase membrane permeation.
The extraction recovery for spiked samplers (10-100 μg) was in the range 93-106 % (except for DMEA 127 %). The precision when sampling three series of ten samplers each was in the range 1.8-7.0 %. Collection efficiencies of > 99.9 % without breakthrough were observed for the studied amines when sampling over 60 min using four sets of two samplers in sequence at a flow rate of 200 mL min-1. Major breakthrough was observed for TEA and DMEA at 800 mL min-1 with collection efficiencies > 82 %. For CHA, DEA, NBA, IPA and AA, the collection efficiencies were > 97 %. The distribution of the aliphatic amines in the sampler was studied by dissection of the denuders (into eight parts) for two different flow rates (200 and 1100 mL min-1). The first parts of the denuder collected the highest amount of aliphatic amines, which then declined throughout the remaining parts. Thus, it was deemed that the denuder was too short to collect all gas phase amines and the presence of the end filter was necessary for efficient collection. No effect was observed on the collection efficiency when samplers were stored for up to 45 days prior to sampling. No degradation of the amines on the sampler was observed when exposed samplers were stored for up to 45 days. When sampling IPA, DEA and TEA over a period of 0.5 - 8 h (n = 6), linear relationships were obtained with correlation coefficients > 0.997. Using sampling flow rates of 50-800 mL min−1, linear relationships were obtained with correlation coefficients > 0.977. Pre- or post-exposure to ambient air for up to 10 h at 25 °C or 50 °C did not affect the sampler performance.
Aliphatic amines, Hydrophilic Interaction Liquid Chromatography, HILIC, dry sampling, liquid chromatography–mass spectrometry, Denuder, filter, sampler
Research subject Analytical Chemistry
IdentifiersURN: urn:nbn:se:su:diva-93921OAI: oai:DiVA.org:su-93921DiVA: diva2:651121