[Determination of bromide ions in total blood, plasma and urine by ion chromatography with amperometric detection]

A direct injection method is described for the determination of bromide ions in plasma and urine by ion chromatography. After being diluted 10-20 times with eluent, the sample was directly injected into an ion chromatograph equipped with amperometric detection. Calibration curves were obtained in the range of 0.05 to 5 micrograms/ml of bromide ions. The coefficient of variation was calculated to be in the range of 1.3-9.4% for 10 repeated measurements and recovery was over 93%. The correlation between analytical results by the proposed method (Y) and those by a spectrophotometric method (X) of 169 urine samples in fumigators was expressed by the equation Y = 0.952 + 1.012X (correlation coefficient (r): 0.952). On the other hand, the correlation between analytical results by the proposed method (Y) and those by neutron activation analysis (X) of 47 total-blood samples in fumigators was expressed by the equation Y = 1.070 + 0.841 X (correlation coefficient (r): 0.931). The correlation between analytical results by the proposed method (Y) and those by neutron activation analysis (X) of 40 plasma samples in healthy workers was expressed by the equation Y = 0.633 + 0.871 X (correlation coefficient (r): 0.955). The proposed method is much more practical than other methods such as the spectrophotometric method and neutron activation analysis in epidemiological studies, because the proposed method is highly accurate and reproducible over longer periods. The proposed method is useful in biological fluid monitoring of bromide ions.