Hyphenation of ultra performance liquid chromatography (UPLC) with inductively coupled plasma mass spectrometry (ICP-MS) for fast analysis of bromine containing preservatives

Ultra performance liquid chromatography (UPLC) was coupled to inductively coupled plasma mass spectrometry (ICP-MS) for fast analysis of three bromine-containing preservatives, monitoring the Br-79 and Br-81 isotopes simultaneously. Due to the efficiency of the 1.7 mu m column packing material, the resolution of the test substances was only slightly affected when the linear flow velocity was increased from 0.5 to 1.9 mms(-1). However, the sensitivity of ICP-MS detection decreased when the linear flow velocity was increased from 0.5 to 1.9 mm s(-1). Analytical figures of merit were determined at an intermediate and at a high linear velocity. The precision was better than 2.2% R.S.D. and regression analysis showed that a linear response was achieved at both flow rates (R-2 > 0.9993, n = 36). The analysis time was less than 4.5 min at a flow rate of 50 mu L min(-1) and limits of detection and quantification were better than 3.3 and 11 mu g Br L-1, respectively. The analysis time was reduced to 2.7 min when the flow rate was increased to 90 mu L min(-1) and limits of detection and quantification were better than 20 and 65 mu g Br L-1, respectively. The method was applied for quantitative analysis of bromine-containing preservatives in commercially available cosmetic products. (c) 2005 Elsevier B.V All rights reserved.