ARS | Publication request: An Ion Chromatographic Method to Determine Methylamines and Amine-N-Oxides in Particulate Matter

Submitted to: American Association for Aerosol Research
Publication Type: Abstract Only
Publication Acceptance Date: July 7, 2009
Publication Date: October 27, 2009
Citation: Erupe, M.E., Liberman-Martin, A., Silva, P.J., Purvis-Roberts, K., Malloy, Q.G., Cocker, Iii, D.R. 2009. An Ion Chromatographic Method to Determine Methylamines and Amine-N-Oxides in Particulate Matter. American Association for Aerosol Research.

Technical Abstract: Several studies have indicated the presence of amines in the particulate phase, believed to result from atmospheric reactions of volatile amines emitted from sources including agriculture. The resulting particulate amines are a combination of cationized (from acid-base reactions) and free base forms. To detect particulate amines, an ion chromatographic method with non-suppressed conductivity detection was adapted from one used for determination of the freshness of seafood. The method allows for the simultaneous detection of methylamines (methylamine, dimethylamine, trimethylamine) and tertiary amine-n-oxides in particulate air samples. The analytes were well separated within 25 minutes by means of cation-exchange chromatography using a 3 mM methanesulfonic acid solution as eluent and an IonPac SCS1 separation column. The effects of different chromatographic parameters on the separation were also investigated. Detection limits for methylamine, dimethylamine, trimethylamine and trimethylamine-N-oxide were 43, 46, 76 and 72 ppb in solution, respectively. The relative standard deviations of the retention time and peak heights were less than 2.4% and 2.1%, respectively. The recoveries were between 78.8% and 88.3%. The method is suitable for determining if amines and amine-n-oxide compounds are significant components of organic nitrogen aerosols. Initial analyses of amine aerosols produced in a smog chamber reaction indicate that amine cations and amine-n-oxides make up less than 10% of the aerosol products from reactions of gas-phase amines.