A novel biosensor of DNA immobilization on nano-gold modified ITO for the determination of mifepristone

A novel DNA modified indium tin oxide (ITO) electrode has been prepared. (3 -Aminopropyl)Trimethoxysilane, gold nanoparticles and DNA molecules are mod ified on the ITO electrode surface by self-assembly and electrochemical tec hniques, respectively. This is a simple, stable, repeatable approach. The m odified electrode can be used to detect mifepristone. A linear dependence o f the peak currents on mifepristone concentrations is observed in the range 4x10(-7)-6x10(-6) mol/L. The relative standard deviation is 4.5% for six s uccessive determinations at 1x10(-6) mol/L solution. The detection limit is 2x10(-7) mol/L.