Comprehensive two-dimensional liquid chromatography–time-of-flight mass spectrometry in the analysis of acidic compounds in atmospheric aerosols

A novel method utilising comprehensive two-dimensional liquid chromatography interfaced to electrospray ionisation time-of-flight mass spectrometry was developed for the determination of organic acids in atmospheric aerosols. The system was applied to the analysis of methanolic extracts of filters from a high volume sampler. The enhanced separation power of two-dimensional separation was demonstrated in the analysis of both rural and urban samples. Quantification was performed for compounds for which standards were available. Limit of detection was 2–200 ng/ml. Average reproducibility of retention times in each dimensions was 0.1%, and average reproducibility of peak areas was 8% (10 μg/ml, n = 3).