A nanostructure label-free DNA biosensor for ciprofloxacin analysis as a chemotherapeutic agent: an experimental and theoretical investigation

Abstract

A nanostructure DNA biosensor based on pencil graphite electrode modified with polypyrrole, single wall carbon nanotubes and ds-DNA (PGE/PP/SWCNTs/DNA) was suggested for the determination of ciprofloxacin. The proposed sensor was characterized using atomic force microscopy (AFM) and electrochemical impedance spectroscopy (EIS) methods. Guanine and adenine signals were used as the sign for investigating the interaction between ciprofloxacin and DNA at the surface of PGE/PP/SWCNTs/DNA. On the other hand, a docking simulations investigation was used for confirming the interaction between DNA and ciprofloxacin. The PGE/PP/SWCNTs/DNA demonstrates a wide dynamic range (0.008–30.0 μM) with an ultrasensitive detection limit of 4.0 nM for the determination of ciprofloxacin using the differential pulse voltammetric (DPV) method. PGE/PP/SWCNTs/DNA showed a good ability for the analysis of ciprofloxacin in drug and urine samples.