Application of Disposable Screen-printed Electrode as an Epirubicin Sensor and Relation among Whole Blood and Tissue Concentrations of Epirubicin

A disposable Multiwalled carbon nanotubes (MWNT) modified screen printed electrode (SPE) was developed for the clinical determination of Epirubicin(EPI). EPI was determined by square wave voltammogram in HAc-NaAc buffer of pH 4.5 in the concentration range of 0.01 to 1.28 mu g/mL. The reproducibility of the analytical signal was characterized by a relative standard deviation smaller than 5%, and the calculated values of detection limits were 8.0 ng/mL. The applicability of the developed method was evaluated by determining EPI in a real sample. After administration of EPI, the concentration-time curve in rabbit blood was analyzed with the MWNT-SPE and the results compared well with those measured by high performance liquid chromatography (HPLC). The concentration-time curve study was also performed to investigate the whole blood-tissue correlation of EPI in mice. Whole blood, heart, liver, kidney and bone marrow samples were collected and analyzed using the validated MWNT-SPE. Good correlations between tissue and whole blood EPI levels were found. These correlations showed the feasibility and rationality of estimating tissue EPI concentration using whole blood, and would be helpful in the routine monitoring of EPI in clinical use.