High‐performance liquid chromatography determination of nitrated polycyclic aromatic hydrocarbons by indirect fluorescence detection

A high‐performance liquid chromatography (HPLC) method for the analysis of nitrated polcyclic aromatic hydrocarbons (NPAHs) is reported. NPAH mixtures were pre‐concentrated using solid‐phase extraction and well resolved on a C 18 column. They were detected using an indirect method involving the quenching of the emission from the fluorophores 5,6,7,8‐tetrahydronaphthol (5,6,7,8‐THN‐1‐OH), 7‐amino‐4‐methyl coumarin (Coumarin 120, COU‐120) and 3‐hydroxy‐4‐(2‐hydroxy‐4‐sulfo‐1‐naphthylazo)2‐naphthalene carboxylic acid (Calcon carboxylic acid, CCA). Linear calibration curves were obtained in the range 1.1 × 10 −9 to 1.1 × 10 −8  mol/L. Using COU 120 as the fluorophore, the detection limit was 2.9 × 10 −10  mol/L for 1‐nitronaphthalene and 2.1 × 10 −11  mol/L for 2‐nitrofluorene. Recoveries of NPAHs from spiked tap water samples were between 88 and 100%. Copyright © 2008 John Wiley & Sons, Ltd.