Determination of Iodine and Bromine Compounds by Ion Chromatography/Dynamic Reaction Cell Inductively Coupled Plasma Mass Spectrometry

Abstract

An inductively coupled plasma mass spectrometer (ICP-MS) was used as an ion chromatographic detector for the speciation of iodine and bromine. Gradient elution using NH4NO3 at pH 10 allowed the chromatographic separation of ionic iodine (I − and IO3 − ) and bromine (Br − and BrO3 − ) species in less than 8 min. Effluents from the ion-exchange column were delivered to the nebulization system of ICP-MS for the determination of I and Br. The potentially interfering 38 Ar 40 ArH + and 40 Ar 40 ArH + at the bromine masses m/z 79 and 81 were significantly reduced in intensity (by approximately two orders of magnitude) by using 0.6 mL min −1 O2 as a reactive cell gas in the dynamic reaction cell (DRC). Moreover, the signal-to-background ratio at iodine mass m/z 127 increased significantly when O2 was used as the reaction gas. The detection limits were in the range of 0.001 -0.002 and 0.03 -0.04 ng mL −1 for various I and Br compounds, respectively, based on the peak height. The relative standard deviation of the peak areas for five injections of a 2 ng mL −1 I − , IO3 − and 20 ng mL −1 Br − , BrO3 − mixture was in the range of 3 -4%. The concentrations of I and Br compounds have been determined in selected water and urine samples. The spike recoveries were in the range of 94 -102% for all of the determinations. This method has also been applied to determine various I and Br compounds in an NIST RM 8435 whole-milk powder reference material and a seaweed sample obtained locally. A microwave-assisted extraction method was used to extract these compounds, which were quantitatively leached with a 10% mass/volume (m/v) tetramethylammonium hydroxide (TMAH) solution in a focused microwave field within a period of 6 min. The major components of I and Br in milk powder and seaweed were I − and Br − .

Concentration of I2, Na, K, Mg and Fe2+ in Soils, Plants, Ash and Salt Samples of Selected Areas of Western Kenya

“…Both the two regions have higher humus content as can be explained by the increase in LOI hence higher organic matter content, which is a great reservoir for iodine. However, there is generally more uptake of iodine by Cyperus papyrus reeds than by Typha Latifolia, 0.164 versus 0.138 which agrees with findings by Zhu et al, (2004) and Wang et al, (2008). Although this is true from the results, iodine translocation from the soil to the reed plants is generally low due to leaching and sorption to soil surfaces.…”

Negative effect of methyl bromide fumigation work on the central nervous system

“…Urinary bromide ion concentrations have also been analysed as an indicator in various studies [ 19 – 21 , 53 ]. Urinary bromide ion concentrations were frequently analysed by gas chromatography [ 21 , 53 ], ion chromatography [ 20 , 53 ] or ICP-MS [ 54 , 55 ]. The HPLC/ICP-MS method was applied by modifying ICP-MS in this study.…”

Characterization of the intragranular water regime within subsurface sediments: Pore volume, surface area, and mass transfer limitations

“…Pre‐equilibration, washing, and tracer monitoring (“release”) stages were conducted as above using a Br amended AGW (350 ppm), with pre‐equilibration times of 2 and 65 d. The bromide samples were acidified and analyzed on an Inductively Coupled Plasma Mass Spectrometer (Perkin Elmer ELAN DRC II). Although the detection limit for Br by ICP‐MS is as low as 0.03 ppb [ Wang and Jiang , 2008], the lowest calibration standard used in this work was 8 ppb. The calibration curve was linear down to this value, and the lowest sample concentration measured was >12 ppb.…”