CE-MS: a useful tool for the identification of water-soluble polar organics in air and vehicular emitted particulate matter.
A CE-ESI/quadrupole-MS method using an ammonium acetate-based BGE (pH 4.7) was developed for the determination of isomeric benzoic acids in atmospheric aerosols and vehicular emission. UltraTrol LN was employed as the pre-coating polymer to suppress the EOF (0.3 x 10(-9) m2 V(-1) s(-1)) and achieve a baseline separation of the studied acids. Good repeatability for migration time (RSD < 1%, N = 10) was obtained without coating regeneration. The high pre-coating stability allowed coupling of CE to MS without ion suppression in the MS. In scanning mode and using field-amplified sample injection with electrokinetic injection (-5 kV for 60 s), LODs (S/N = 3) ranged from 2.5 to 6 microg/L for standard target analytes prepared in DI water. In the presence of 100 mg/L of sulfate (added to simulate a sample matrix), LODs ranged from 8 to 90 microg/L. Several isomeric aromatic acids could be separated in atmospheric and diesel-engine-emitted particulate matter extracts based on their different acidities. Additional measurements with a flow infusion ESI Fourier transform ion cyclotron resonance MS were used for further structural information acquisition on the unknown compounds and allowed their formula to be proposed.
Analysis and Air Quality Section, Air Quality Research Division, Atmospheric Science and Technology Directorate, Environment Canada, Ottawa, Ont., Canada.
Mahmoud M
MM
Yassine
Ewa
E
Dabek-Zlotorzynska
Philippe
P
Schmitt-Kopplin
D000336:Aerosols / Q000032:analysis; D000388:Air; D000393:Air Pollutants / Q000032:analysis; D019075:Electrophoresis, Capillary / Q000379:methods*; D013058:Mass Spectrometry / Q000379:methods*; D052638:Particulate Matter / Q000032:analysis*; D001335:Vehicle Emissions / Q000032:analysis*; D014867:Water / Q000737:chemistry
D000336:Aerosols; D000393:Air Pollutants; D052638:Particulate Matter; D001335:Vehicle Emissions; D014867:Water