Determination of elevated concentrations of bromine in serum by ICP-MS and ICP-OES

Abstract

The inorganic and organic components of 100-fold diluted serum enhance the signal of ⁷⁹Br⁺ in ICP-MS by about 13%. Sodium and albumin are the main causes of the effect. Different calibration procedures were investigated to compensate for the enhancement interference. The effect of albumin could not be mimicked sufficiently by use of low molecular weight sources of carbon such as sucrose. Plasma substitute proved a convenient material and can be used, in most circumstances, to matrix match for serum. Plasma substitute also has the advantage of containing no endogenous bromine. The proposed ICP-MS method produced results for Br in serum in agreement with those of an ICP-OES method. The detection limits of the ICP-MS and ICP-OES methods were 0.09 and 0.8 mg L⁻¹, respectively.