Determination of mono- and dicarbonyls in the atmosphere using gas chromatography/mass spectrometry after PFBHA derivatization
五氟苄基羟胺衍生与GC／MS联用分析大气中的单羰基化合物和多羰基化合物

A method for detecting 14 mono- and 2 dicarbonyl compounds in one run was established. The carbonyls were collected on solid sorbent (Tenax-TA) coated with derivating agent O-(2,3,4,5,6-Pentafluorobenzyl) hydroxylamine hydrochloride (PFBHA), followed by solvent desorption, concentration and gas chromatography/mass spectrometry analysis. The coating amount and the sampling flow rate were optimized. The results showed that the best collection efficiency was achieved when the coating amount was 260 nmol and the sampling flow rate was 50 mL·min-1 for a loading of 50 mg Tenax-TA. The limits of detection were in the range of 0.54~3.83 ng·m-3. The relative standard deviations of parallel samples were 1.0%~14.2% and the recoveries of the spiked standards were 89.2%~113.8%. The time resolution could be 30 min to 8 h for ambient air sampling. The method was successfully applied to measure 16 mono- and dicarbonyls in the ambient air of Baoshan District of Shanghai and the detected carbonyls have significant diurnal variation.