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 79Br and 81Br isotopes simultaneously. Due to the efficiency of the 1.7 μm 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 mm s−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 (R2 > 0.9993, n = 36).The analysis time was less than 4.5 min at a flow rate of 50 μL min−1 and limits of detection and quantification were better than 3.3 and 11 μg Br L−1, respectively. The analysis time was reduced to 2.7 min when the flow rate was increased to 90 μL min−1 and limits of detection and quantification were better than 20 and 65 μg Br L−1, respectively. The method was applied for quantitative analysis of bromine-containing preservatives in commercially available cosmetic products.