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.
Yassine
Mahmoud M
MM
Analysis and Air Quality Section, Air Quality Research Division, Atmospheric Science and Technology Directorate, Environment Canada, Ottawa, Ont., Canada.
Dabek-Zlotorzynska
Ewa
E
Schmitt-Kopplin
Philippe
P
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