New strategy in electrochemical investigation of DNA damage demonstrated on genotoxic derivatives of fluorene

Abstract

• Electrochemical DNA biosensor based on a glassy carbon electrode was optimized and characterized. • Comprehensive electrochemical biosensing approach was used to detect DNA damage. • DNA damage was detected after interaction with derivatives of fluorene. • Simple electrochemical DNA biosensor was applied for fast and sensitive detection. • Investigation of derivatives of fluorene with dsDNA present in solution was used. In this work, a simple and fast electrochemical DNA biosensor based on a glassy carbon electrode (GCE) was prepared by adsorbing double-stranded DNA (dsDNA) from salmon sperm as a biorecognition layer onto the GCE surface. The dsDNA/GCE biosensor was characterized using modern imaging techniques. The prepared dsDNA/GCE biosensor was used for detection of dsDNA damage by 2-aminofluorene (2-AF), its metabolite 2-acetylaminofluorene (2-AAF), and 2,7-diaminofluorene (2,7-DAF). The electrochemical investigation of the interaction between the selected analytes and dsDNA was conducted using a combination of several electrochemical detection techniques (representing a comprehensive electrochemical biosensing approach allowing an overall assessment of dsDNA damage, even when the intrinsic voltammetric signals of the studied analytes overlap with the dsDNA signals): (i) cyclic voltammetry (CV), square wave voltammetry (SWV), and electrochemical impedance spectroscopy (EIS) at the dsDNA/GCE biosensor, and (ii) differential pulse voltammetry (DPV) for measurements directly in solution at the bare GCE. The changes in dsDNA structure caused by structurally similar analytes were observed. The mutual interaction between derivatives of fluorene and dsDNA caused damaging effects of the test substances on the dsDNA structure in vitro .