Voltammetric behavior of doxorubicin at a renewable silver-amalgam film electrode and its determination in human urine

Voltammetric characterization of doxorubicin (DOX) and its determination using a renewable silver-amalgam film electrode (Hg(Ag)FE) was performed by direct cathodic square-wave voltammetry (SWV) and by the highly sensitive adsorptive square-wave voltammetry (AdSWV) in aqueous Britton-Robinson buffer solutions as supporting electrolyte (pH 2.0-8.0). The Hg(Ag)FE response of DOX was monitored in the potential range between -0.20 and -0.80 V. For the trace level analysis the method optimization showed that the optimal conditions were: the pH 6.0, the accumulation potential -0.20 V, and the accumulation time 140 s. In the model solutions, DOX was determined in the concentration range of 4.99-59.64 ng mL−1. The developed AdSWV method was applied for the determination of DOX in spiked human urine sample. The lowest concentration of DOX of 9.89 ng mL−1 was determined with the relative standard deviation less than 6%.