Determination of low-molecular-mass carboxylic acids in atmospheric aerosol and vehicle emission samples by capillary electrophoresis.
A method is developed for the determination of a large number of airborne and vehicle-emitted low-molecular-mass mono- and dicarboxylic acids using capillary electrophoresis with indirect UV detection. A background electrolyte (BGE) consisting of 2,6-naphthalenedicarboxylic acid and tetradecylmethylammonium bromide, adjusted to pH 6.2 with 2,2-bis(hydroxymethyl)-2,2',2"-nitrilotriethanol, is employed. Separations are robust using the buffered BGE, proper rinse steps, and constant current mode with migration time variations less than 3% RSD on a day-to-day basis, using different capillaries and performed by different analysts. Detection limits are at the tens of microg/l level using pressure injection. A comparison of the CE method with ion chromatography is also made.
Dabek-Zlotorzynska
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E
Analysis and Air Quality Division, Environmental Technology Centre, Environment Canada, Ottawa, Ontario. dabek.ewa@etc.ec.gc.ca
Piechowski
M
M
McGrath
M
M
Lai
E P
EP
D000336:Aerosols / Q000737:chemistry*; D001272:Atmosphere; D002264:Carboxylic Acids / Q000032:analysis*; D019075:Electrophoresis, Capillary / Q000379:methods*; D008970:Molecular Weight; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013056:Spectrophotometry, Ultraviolet; D001335:Vehicle Emissions / Q000032:analysis*
D000336:Aerosols; D002264:Carboxylic Acids; D001335:Vehicle Emissions