Determination of bromate in highly saline samples using CZE with on-line transient ITP.

We developed CZE with direct UV detection for the determination of bromate in highly saline samples such as seawater and salts using transient ITP as an on-line concentration procedure. The following optimum conditions were established: BGE, artificial seawater containing no bromide adjusted to pH 3.0; detection wavelength, 210 nm; vacuum injection period of sample, 18 s (378 nL); terminating ion solution, 600 mM sodium acetate; vacuum injection period of the terminating ion solution, 7 s (147 nL) for seawater and 12 s (252 nL) for salts; applied voltage, 7 kV with the sample inlet side as the cathode. The LOD for bromate was 30 microg/L (BrO(3) (-)-Br) with S/N of 3. The respective values of the RSD of the peak area, peak height, and migration time for bromate were 6.4, 1.5, and 0.51%. Seawater and salt samples, with bromate added, were analyzed using this method. The recovery of bromate in seawater samples was 85-105%. Linear regression equations relating area and height responses to concentration for bromate were obtained using the salt samples.