Determination of interaction mode between DNA and antineoplastic drugs and development of electrochemical genosensor

In this study, an electrochemical genosensor was preperad for determination of antineoplastic drugs 5-Fluorouracil (5-FU) and 2-Thiouracil (2-TU) and interaction modes between dsDNA and drugs were investigated. For his purpose, bromocresol purple (BCP) monomer was electrochemically coated on the suface of the glassy carbon electrode (GCE). The surface characterization of GCE/P(BCP) was investigated via FT-IR-ATR, Scanning electron microscope (SEM) and EDX analysis was conducted. dsDNA was immobilized on to GC/P(BCP) electrode and proposed electrode was called as GCE/P(BCP)/dsDNA. The electron transfer properties of prepared electrodes were studied by using electrochemical impedance spectroscopy (EIS) ve cyclic voltammetry techniques (CV). The electrochemical determination of drugs were carried out using GC/P(BCP)/dsDNA electrode via monitoring of guanine signal. The linear working range for 5-FU was determined as 1-50 mg L-1. For 2-TU, the linear working range was 0,1-50 mg L-1. The effects of current interference species on the oxidation guanine signal were studied. Finally, analytical applicability of the prepared genosensor was investigated and the recovery values (%) were calculated. It can be concluded that both of drugs can bind to dsDNA with intercalation binding mode.