Fluorimetric determination of bromate by ion-exchange separation and post-column derivatization

Abstract

Abstract. For the determination of bromate in drink-ing water a stopped-flow post-column reaction was developed following the separation of bromate from the matrix by an anion-exchange column. In the postcolumn reaction the analyte was used to oxidize the azo dye sulfonaphtholazoresorcinol, SNAR, and the residual amount was converted into a fluorescent binuclear complex by an excess of gallium ions. The fluorescence was monitored at 585nm, with a maximum excitation wavelength at 521 nm. The determination of bromate is based on the decrease of the fluorescence intensity with increasing bromate concentration. The given hydrodynamic parameters and the condition of equal flow rates of the two branch streams at each Tpiece have to be considered as an important criterion for the experimental set-up. The volume flows and the concentrations required for the reagent solutions in the influent of each T-piece were determined as a result of batch experiments and theoretical considerations. The limit of detection was 0.28 gg L-lbromate for the flow method, which shows linearity up to 15 ggL -1 bromate.

Bromate analysis in groundwater and wastewater samples

“…Detection within a 0.5-100 mg L À1 range was noted without sample pre-treatment. 18 Sulfonaphtholazoresorcinol reacts with bromate to give a decrease in fluorescence at 585 nm, with a calibration range of 0.28-15 mg L À1 bromate suggested by Gahr et al 19 Fuschin can react with bromate in acidic medium, forming a strongly-absorbing product at 530 nm. A range of 0.1-100 mg L À1 was noted by Achilli and Romele 20,21 using a standard carbonate/bicarbonate eluent, with Valsecchi et al 22 trialling a tetraborate eluent and sample size up to 1.5 ml with no pre-treatment to improve resolution.…”

Formulation of Rapid Method for Detection and Estimation of Bromate in Serum and Confectionaries Consumed in Enugu, Nigeria

“…There are several existing methods for the determination of bromate, all with their different complexities, colourimeteric method, [9], spectrophometric method [10] capillary electrophoresis, [11]mass spectrometry flow injection analysis [12].whichever method that is used, the complex matrix in samples of bakery products dictate that a degree of sample pretreatment is required. Secondly no conventional spot method for spot checks at retail outlets has been developed.…”

Flow-Injection Spectrophotometric Determination of Bromate in Bottled Drinking Water Samples Using Chlorpromazine Reagent and a Liquid Waveguide Capillary Cell

“…11 As potential alternatives, spectrophotometric methods were developed resorting to different redox reactions like the oxidation of phenothiazines, 12,13 fuchsin, 14 pyrogallol red, 15 o-dianisidine 16 or sulfonaphtholazoresorcinol. 17 Phenothiazines (including chlorpromazine, prochlorperazine trifluoperazine, and thioridazine) show analytical characteristics that make them particularly interesting for implementation in a flow-based analytical method. The reaction is based on the formation of a colored radical cation; the reaction occurs in a highly acidic media, and the quantity of the excess acid has an important role in the extension of the reaction, as discussed in detail in previous publications.…”