Analysis of leachable and total trace metals in air particulate matters by capillary electrophoresis

A new analytical procedure was developed for simultaneous determination of ammonium, leachable and total metals in fine and coarse air particulate matters using a new capillary electrophoresis (CE) procedure, with a new buffer system containing 10 mM histidine, 2 mM 18-crown-6 and 8 mM lactic acids with pH adjusted to 4.0. A two complexes system, 18-crown-6 ether and lactic acid, was developed to solve the co-migration problem of NH4+ and K+ and to give satisfactory separation of transition metals. Satisfactory separation and quantitation of NH4+, K+, Ca2+, Na+, Mg2+ and Zn2+ were obtained using the CE procedure developed for both leachable and total metals in coarse (10-3 mu m) and fine (< 3 mu m) air particulate matters. Wide working ranges (ppb to ppm range) and sensitive detection limits (ppb) were obtained for the cations investigated. The reliability was established by parallel method comparison with the ICP-AES method. The analytical procedure developed is shown to provide a quick, sensitive, precise and economic method for simultaneous determination of ammonium, leachable and total metals in air particulate matters. (C) 1998 Elsevier Science B.V.