Abstract
Doxorubicin (DOX) represents an anthracycline-based antitumor and antibiotic medication. DOX determination in body fluids is relevant for treatment, monitoring, and individual dosage optimization.
Two novel methods of DOX determination have been compared in this manuscript: i) differential pulse cathodic stripping voltammetry (DPCSV) on a polished silver solid amalgam electrode (p-AgSAE) in a specially designed micro-volume voltammetric cell (MVVC) and ii) differential pulse voltammetry (DPV) on a polarized liquid/liquid interface represented by a supported membrane prepared by impregnating a polyvinylidenfluoride microporous filter with a room-temperature ionic liquid (RTIL) tridodecylmethylammonium tetrakis[3,5-bis(trifluoromethyl)phenyl]borate (TDMA-TFPB). Moreover, elimination voltammetry with linear scan (EVLS) has been applied for elucidation of controlling reaction processes observed at the p-AgSAE.
DPCSV method on the p-AgSAE is applicable for the determination of DOX in the linear dynamic range (LDR) from 0.6 to 10 mu mol L-1, with the limit of detection (LOD) of 0.44 mu mol L-1. Applicability of this method was verified on analysis of spiked samples of tap water (recovery 100.6 +/- 6.6%, relative standard deviation (RSD) 5.9%, on the DOX level of 1.0 mu mol L-1) and human urine (recovery 100.7 +/- 6.6%, RSD 4.3%, on the DOX level of 1.0 mu mol L-1).
Using the above-mentioned innovative liquid/liquid interface method, similar results have been achieved (LOD of 0.84 mu mol L-1 , LDR from 1 to 40 mu mol L-1). Nevertheless, due to the presence of some interfering compounds and of charged lipophilic compounds, this method must be preceded by a separation step in the case of body fluids analysis.