Title

Ultrahigh-resolution FT-ICR mass spectrometric identification of water-soluble AOM in nonurban organic aerosols

Document Type

Conference Proceeding

Publication Date

8-11-2011

Abstract

Water-soluble atmospheric organic matter (AOM) is a complex mixture of thousands of organic compounds which may have significant influence on the climate-relevant properties of atmospheric aerosols. To understand the potential influence, the water-soluble fraction of ambient aerosols was analyzed by positive and negative electrospray ionization Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometry. Approximately 4000 negative and 1000 positive chemical formulas were identified. The formulas contained carbon, hydrogen, oxygen, nitrogen, and sulfur atoms over the mass range of 100-800 in both modes. The range of double bond equivalence (DBE) values, the average O/C and H/C ratios of the negative ions were 0-14, 0.53, and 1.48, respectively. The range of DBE values, the average O/C and H/C ratios of the positive ions were 0-17, 0.33, and 1.40, respectively. Despite the range of DBE values, the majority compounds were found in the aliphatic region of the van Krevelen diagram.

Publication Title

242nd American Chemical Society National Meeting & Exposition