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 solidphase 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{pipe}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).