Abstract
A method is described for the determination of acrylic acid at nanomolar concentrations in complex aqueous samples. The method involves extraction and preconcentration from the acidified sample using tri-n-octylphosphine oxide dissolved in methyl tert-butyl ether and subsequent derivatization with pentafluorobenzyl bromide using 18-crown-6 as catalyst. The pentafluorobenzyl ester of acrylic acid is then quantified by capillary gas chromatography with electron capture detection. The limit of detection is about 6 femtomole, corresponding to a concentration of 3 nmol/l of the acid in a 100-ml sample. Acrylic acid has been measured in aqueous samples, including natural waters, to illustrate the performance of this procedure. (Author 's abstract)