Radiocarbon Analysis of Atmospheric Formaldehyde Using Cystamine Derivatization

TitleRadiocarbon Analysis of Atmospheric Formaldehyde Using Cystamine Derivatization
Publication TypeJournal Article
Year of Publication2009
AuthorsShen, H, McNichol, AP, Xu, L, Gagnon, A, Heikes, BG
Date PublishedAUG 1
Type of ArticleArticle

A compound specific radiocarbon analysis method was developed to evaluate the C-14 composition of atmospheric formaldehyde. In this method, gaseous formaldehyde was collected with a high-volume air sampler using glass-fiber filters pretreated with sodium bisulfite. Collected formaldehyde was then released into water and derivatized with cysteamine to thiazolidine. The thiazolidine was extracted into dichloromethane and concentrated by evaporation. Concentrated thiazolidine was separated from other compounds using preparative capillary gas chromatography and uniquely collected as a phosphate salt with a fraction collector. The C-14 composition of the salt was analyzed by accelerator mass spectrometry after combustion to CO2 and subsequent reduction to graphite. In a pilot study, ambient formaldehyde samples collected on the roof of the CACS building at Narragansett Bay Campus, Narragansett, RI, showed a significantly larger fraction of fossil carbon than modern carbon.