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Evaluation of stationary phases and gas chromatographic detectors for determination of amines in water.

For the first time, a systematic overview deals with the advantages and disadvantages of several stationary phases (polar and non-polar) and gas chromatographic detectors (flame ionization detector, nitrogen-phosphorus detector and MS) for the determination of 27 amines (aliphatic and aromatic amines and N-nitrosamines) in water samples. To increase sensitivity (250 mL of sample was eluted with 150 μL of solvent) and matrix elimination, an automatic SPE system was employed prior to GC determination. The best results in terms of resolution and retention times were achieved using a column coated with 5% phenyl-dimethylpolysiloxane (DB-5). Capacity factor (k) values for the 27 amines increased with the rise in the polarity of the stationary phase, ranging from 3.0-27.7 and 2.2-14.4 for polar (polyethylene glycol) and non-polar (DB-5) columns, respectively. The detection limits of the method were 0.9-9 μg/L for flame ionization detector, 8-95 ng/L for nitrogen-phosphorus detector and 0.2-6.3 ng/L for MS. The precision was similar for the three detectors (RSD, 3.7-6.0%). The GC-MS method was applied with a high degree of accuracy and precision to determine amines in real samples including tap, river, pond, well, swimming pool and wastewaters.