Highly selective spectrophotometric flow-injection determination of trace amounts of bromide by catalytic effect on the oxidation of m-cresolsulfonephthalein by periodate

• Published in: Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy Molecular and biomolecular spectroscopy, 2004-07, Vol.60 (8), p.2053-2057
• Main Authors: Ensafi, Ali A, Rezaei, B, Nouroozi, S
• Format: Article
• Language: English
• Subjects: Bromide; Bromides - analysis; Catalysis; Catalytic; FIA; Flow Injection Analysis - instrumentation; Flow Injection Analysis - statistics & numerical data; m-Cresolsulfonephthalein; Oxidation-Reduction; Periodic Acid; Phenolsulfonphthalein - analogs & derivatives; Phenolsulfonphthalein - chemistry; Reproducibility of Results; Sensitivity and Specificity; Spectrophotometry - instrumentation; Spectrophotometry - methods; Water - analysis
• ISSN: 1386-1425
• DOI: 10.1016/j.saa.2003.11.003

A new flow-injection method is reported for the determination of bromide. The method is based on catalytic effect of bromide on the oxidation of m-cresolsulfonephthalein by periodate in acidic media. The reaction was followed spectrophotometrically by measuring the decrease in absorbance at 528 nm. The influence of pH, reagent concentration and manifold variables on the sensitivity was studied. Under optimum conditions, a calibration graph was obtained in the range of 0.160–20.00 μg ml −1 bromides with a limit of detection of 0.150 μg ml −1 bromide. The relative standard deviation for ten replicate measurement of 1.0 μg ml −1 bromide was 2.1%. The influence of potential interfering ions on the selectivity was studied. The method successes to measure bromide in the presence of other halide ions. The method was used to measure bromide in river water and tap water.