Iron oxide-chitosan hybrid nanobiocomposite based nucleic acid sensor for pyrethroid detection

Nucleic acid sensor has been fabricated via immobilization of single standard calf thymus deoxyribose nucleic acid (ssCT-DNA) onto chitosan (CH)-iron oxide (Fe3O4) nanoparticles based hybrid nanobiocomposite film deposited onto indium-tin-oxide (ITO) coated glass for pyrethroids [cypermehtirn (CM) and permethrin (PM)] detection. The ssCT-DNA immobilized onto CH-Fe3O4 nanocomposite/ITO electrode has been characterized using scanning electron microscopy (SEM), UV–visible, Fourier transform infrared (FTIR) spectroscopy, electrochemical impedance spectroscopy (EIS) and differential pulse voltammetry (DPV) techniques. This disposable ssCT-DNA/CH-Fe3O4 nanobiocomposite/ITO bioelectrode is stable for about two months under refrigerated conditions and can detect CM (0.0025–2 ppm) and PM (1–300 ppm) using DPV technique within 25 s and 40 s, respectively.