UV-detection capillary electrophoresis for benzo[a]pyrene and pyrene following a two-step concentration system using homogeneous liquid–liquid extraction and a sweeping method

Abstract

10−9 mol l−1 levels of polycyclic aromatic hydrocarbons (PAHs) suspected for certain noxious materials can be determined and separated by UV-detection capillary electrophoresis following a two-step concentration system. When the conditions of the homogeneous liquid–liquid extraction were [THF]T = 5 vol%, [HCl]T = 0.66 mol l−1, and [PFOA]T = 2 × 10−3 mol l−1 (i.e., the volume of sample solution; 50 ml → sedimented phase; 30 μl), the extraction percentages of benzo[a]pyrene (Bap) and pyrene (Py) at 10−6 mol l−1 were 102 and 97.5%, respectively. Also, when the total concentration factor(volume ratio), which includes that of the sweeping method, was 8335-fold, the determination range of Bap was 6.4 × 10−9–8.0 × 10−7 mol l−1 and for Py, 8.0 × 10−9–7.0 × 10−7 mol l−1. The detection limits (3σ) of Bap and Py were 1.6 × 10−9 and 4.8 × 10−9 mol l−1, respectively.