Assay of urinary 8-hydroxy-2'-deoxyguanosine by capillary electrophoresis with spectrophotometric detection using a high-sensitivity detection cell and solid-phase extraction.

A sensitive capillary electrophoretic method featuring spectrophotometric detection using a commercial Z-cell was devised for the assay of 8-hydroxy-2'-deoxyguanosine (8OHdG) in human urine. Solid-phase extraction (SPE) based on hydrophilic-lipophilic-balanced RP sorbent was utilized for urine sample pretreatment and analyte preconcentration. The separation was carried out in conventional fused-silica capillaries employing a Z-cell with hydrodynamic sample injection (at 50 mbar for 12 s).