Spectrophotometric determination of bromide in water using the multisyringe flow injection analysis technique coupled to a gas-diffusion unit

Abstract

A novel spectrophotometric method for the determination of bromide has been developed using the Multisyringe Flow Injection Analysis technique (MSFIA). This method is based on the decolorization of methylene blue by the bromine released from the oxidation of bromide by bromate under acidic conditions. By incorporating a gas-diffusion unit into the MSFIA system the transferred bromine reacts with methylene blue in the acceptor stream. The decrease of the methylene blue absorbance is monitored at 745 nm. The oxidation conditions are not strong enough to oxidize chloride to chlorine, which is a major component of both natural and seawater. The proposed method provides linearity for the determination of bromide over a range of 1 Â 10 À5 mol L À1 to 6 Â 10 À5 mol L À1 in 5 Â 10 À2 mol L À1 of chloride, with a correlation coefficient (r 2 ) of 0.9939, and a precision of 3.1% (%RSD for 3 Â 10 À5 mol L À1 Br À in 5 Â 10 À2 mol L À1 Cl À , n ¼ 10). The limit of detection (3s) is 0.5 Â 10 À5 mol L À1 . The proposed method has been applied to the determination of Br À in water samples, obtaining recoveries in the analysis of spiked tap, natural, and seawater samples in the range of 90-106%.

Thiourea Based Dipodal Receptor Development for Electrochemical Detection of Br− Ion in an Aqueous Medium

“…Traces of bromide are found in various sources of water 9. High amount of bromide ion is found in marine water which is mainly estimated near to 68 mg/L whereas its amount varies from source to source and country to country, which is typically from 0.004–1.1 mg/L 10. Bromide widely exists in various biological fluids especially in saline, urine, serum, saliva etc.…”

Development of electrochemical biosensors and sensors for the determination of interest analytes

“…Different methods based on volumetric techniques [334], spectrophotometry [325,[335][336][337][338], colorimetry [328,[339][340][341], ion-exchange chromatography [342,343], inductively coupled plasma mass spectrometry [344,345], spectrofluorimetry [321,331,346,347], molecular absorption spectrometry [330] and neutron activated analysis [336], have been used to determine bromide content in several types of samples. Despite the high accuracy and detection limits achieved by some of these techniques, still exists lack of selectivity, requiring complicated pretreatments and bromide extraction steps from the samples.…”

“…The typical concentrations of bromide in water are approximately 0.12 µM in desalinated water, 6 µM in fresh water, being usually present in higher concentrations in seawater (0.75 -0.88 mM) [322]. The problematic comes from the presence of higher concentrations of the anion, that result in the formation of undesirable brominated disinfection byproducts (DBPs), during the oxidizing disinfection treatments by chlorine or ozone, used to obtain potable water [323][324][325][326][327][328]. These DBPs, are associated with adverse impacts to human health, being highly carcinogenic at very low concentrations.…”

“…These DBPs, are associated with adverse impacts to human health, being highly carcinogenic at very low concentrations. In addition, the presence of this anion is a potential source of bromine, which is highly reactive with natural organic matter [325,329].…”

“…Therefore, analytical methodologies to monitoring of bromide anions in drinking waters, including bottled ones is an important task [325,328,331].…”