Determination of anthracycline antibiotics doxorubicin and daunorubicin bycapillary electrophoresis with UV absorption detection

Sweeping preconcentration and electrokinetic injection was used for the cap illary electrophoretic analysis of trace amounts of biologically active ant hracyclines with UV absorption detection. Phosphate buffer (100 mM), pH 2.5 , with addition of 40% v/v methanol was used as background electrolyte (BGE ). Sodium dodecyl sulfate (150 mM) was added to BGE in the inlet vial as th e sweeping agent. The system enables effective separation of anthracyclines as well as cleanup from matrix impurities. Sweeping preconcentration of sa mple provides an excellent detection limit (1 x 10(-9) mol L-1). The method was applied for the determination of therapeutic levels of doxorubicin in real plasma samples.