Sensitive and robotic determination of bromate in sea water and drinking deep-sea water by headspace solid-phase micro extraction and gas chromatography–mass spectrometry

Abstract

A robotic method has been established for the determination of bromate in sea water and drinking deep-sea water. Bromate in water was converted into volatile derivative, which was measured with headspace solid-phase micro extraction and gas chromatography–mass spectrometry (HS-SPME GC–MS). Derivatization reagent and the HS-SPME parameters (selection of fibre, extraction/derivatization temperature, heating time and; the morality of HCl) were optimized and selected. Under the established conditions, the detection and the quantification limits were 0.016μgL−1 and 0.051μgL−1, respectively, and the intra- and inter-day relative standard deviation was less than 7% at concentrations of 1.0 and 10.0μgL−1. The calibration curve showed good linearity with r2=0.9998. The common ions Cl−, NO3−, SO42−, HPO42−, H2PO4−, K+, Na+, NH4+, Ca2+, Mg2+, Ba2+, Mn4+, Mn2+, Fe3+ and Fe2+ did not interfere even when present in 1000-fold excess over the active species. The method was successfully applied to the determination of bromate in sea water and drinking deep-sea water.