Determination of 1-hydroxypyrene in human urine by HPLC with electrochemical detection at a boron-doped diamond film electrode
Abstract
A high-performance liquid chromatographic method with electrochemical detection (HPLC-ED) at a boron-doped diamond film electrode with preliminary separation and preconcentration by solid-phase extraction (SPE) has been developed for the determination of 1-hydroxypyrene (1-HP) in human urine. 1-HP is among the most widely used biomarkers of exposure to polycyclic aromatic hydrocarbons. Optimal HPLC-ED conditions have been found: mobile phase methanol-0.05 mol L-1 phosphate buffer pH 5.0 (80:20, v/v), detection potential +1,000 mV versus Ag/AgCl (3 mol L-1 KCl), and flow rate 0.8 mL min(-1).
For SPE, LiChrolut(A (R)) RP-18 E cartridges were used. The extraction yield was (87.0 A +/- 5.8) % (n = 5).
The concentration dependence of 1-HP was measured in the concentration range from 0.01 to 10 mu mol L-1 (2.18-2,180 mu g L-1) using methanolic solutions resulting from the SPE pretreatment of spiked human urine samples. The limit of detection (signal-to-noise ratio 3) and the limit of quantification (signal-to-noise ratio 10) of the biomarker were 0.013 mu mol L-1 (2.84 mu g L-1) and 0.043 mu mol L-1 (9.39 mu g L-1), respectively, which is sufficient for its determination in the urine of persons exposed to polycyclic aromatic hydrocarbons.