Ultrasonic assisted extraction combined with titanium-plate based solid phase extraction for the analysis of PAHs in soil samples by HPLC-FLD

In this work, ultrasonic assisted extraction combined with solid phase extraction (SPE) was applied in the analysis of polycyclic aromatic hydrocarbons (PAHs) in environment samples. A titania nanotubes/titanium plate was modified with n-octadecanethiol monolayer-protected Ag nanoparticles, and developed as the adsorbent in SPE of PAHs. Six different PAHs in soil samples were analyzed with high performance liquid chromatography-fluorescence detection. The experiment conditions including the deposition time of Ag nanoparticles, extraction solvent properties, the amount of extraction solvent, the amount of organic modifier, extraction time, and desorption solvent properties were optimized. Under the optimized conditions, good linearity and low limits of detection of 0.0015–0.4 ng g−1 were obtained. The analysis of PAHs in real soil samples gave satisfactory recoveries ranging from 70.32% to 115.51% with 3.14%–13.56% intra-day relative standard deviations (RSD) and 4.92%–14.87% inter-day RSD.