Voltametrické stanovení stopových množství 2-aminofluoren-9-onu s předřazenou prekoncentrací analytu pomocí extrakce na tuhou fázi
Optimum conditions were found for the determination of nanomolar and subnanomolar concentrations of genotoxic 2-aminofluoren-9-one (2-AFN) by adsorptive stripping differential pulse voltammetry (AdSDPV) at a hanging mercury drop minielectrode (HMDmE) after preliminary separation and preconcentration by solid-phase extraction (SPE) in LiChrolut RP-18 E (500 mg) columns. The adsorbed analyte was eluted with acetone, the solution then evaporated to dryness, and the residue dissolved in acetate buffer (pH 4.0) (AcB). A sample was then measured by AdSDPV at the HMDmE, with the accumulation potential 100 mV (vs. Ag|AgCl in 1 mol l–1 KCl) and the accumulation time 120 s. Linear calibration curves were obtained for 2·10–11 – 1·10–9 mol l–1 2-AFN, with the limit of quantification (LQ) ≈ 4·10–11 mol l–1. The method was verified by the determination of 2-AFN in model samples of drinking and river water at concentrations 4·10–11 – 1·10–9 and 2·10–10 – 1·10–9 mol l–1 (LQ ≈ 6·10–11 and 4·10–10 mol l–1, respectively).