Determination of bromide using flow injection and chemiluminescence detection

Abstract

A method is described for the determination of bromide ion in the range 1–100 µg ml^–1(correlation coefficient 0.9996) with a detection limit of 3.75 pg and a coefficient of variation of ⩽1%. The optimum parameters were studied and were found to be the following: HNO₃, 0.25 M; luminol, 0.01 mM; H₂O₂, 10 mM; KBrO₃, 100 mM; and flow-rate, 3 ml min^–1. The interference from several cations was overcome by using batch and continuous exchange with a strong cation-exchange resin. Up to 100 µg ml^–1 of chloride ion and 1 µg ml^–1 of iodide ion did not interfere with the determination of 10 µg ml^–1 of bromide; 113 samples can be injected per hour.