Determination of polycyclic aromatic hydrocarbons on SMA-EGDMA polymeric mononlith column by capillary electrochromatography

Abstract

In this study, a reversed-phase C18 polymeric monolith column of stearyl methacrylate-co-ethylene glycol dimethacrylate (SMA-EGDMA) was prepared and used to separate polycyclic aromatic hydrocarbons (PAHs) by capillary electrochromatography. The prepared column exhibits a good efficiency of 20,000 plates per m for naphthalene. The separation conditions for PAHs were systematically optimized. The optimized condition for the mobile phase was acetonitrile/10 mM ammonium acetate, pH 7 (80/20, v/v), and the applied voltage was set at 28 kV. Subsequently, an on-line concentration was employed to the CEC separation and by changing injection time a dramatic improvement was observed in the detection sensitivity up to 50-fold enhancement, achieving nanogram level with almost no loss of resolution. Six polycyclic aromatic hydrocarbons (naphthalene, fluorene, phenanthrene, fluoranthene, pyrene, benz[a]anthracene) showed good linearity with linear correlation coefficient R > 0.99. Reproducibility of the column was investigated. Relative standard deviations of migration time (n = 5) and peak area (n = 5) were in the range of 4.71–4.93% and 4.88–6.65%, respectively, for the six polycyclic aromatic hydrocarbons on the SMA-EGDMA polymeric monolith column. The percentage recoveries of six PAHs including naphthalene, fluorene, phenanthrene, fluoranthene, pyrene and benz[a]anthracene in East Lake water samples at three different concentrations are 93.7–102.5, 98.6–108.1, 92.6–105.9, 95.2–102.1, 91.8–105.4, and 100.9–103.7, respectively.