This study describes a newion chromatography method using a low-capacity anion exchange column with amperometric and absorbance detection for rapid and simultaneous determination of
Br− and NO3− in contaminated waters where one of these ions is present in excess compared to other. The use of two detectors overcomes the problem of baseline separation for
Br− and NO3− for accurate quantification, which was commonly encountered when using a low-capacity anion exchange column and suppressed conductivity detection mode. The method achieved accurate quantification of these two ions without requirement of baseline separation. The accuracy of 2.8% for
NO3− was determined using a quality control sample obtained from UN GEMS/Water PE Study No. 6. The detection limits for
Br− and NO3− were 20 and
6µg l−1 (25µl sample), respectively. Linearity of these two ions was over three orders of magnitude with a correlation coefficient >0.998. The influence of potential interfering ions was also studied followed by the determination of
Br− and NO3- in seawater, unsaturated zone water, soil extract and groundwater.
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