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. (3Aminopropyl)Trimethoxysilane, gold nanoparticles and DNA molecules are modified on the ITO electrode surface by self-assembly and electrochemical techniques, respectively. This is a simple, stable, repeatable approach. The modified electrode can be used to detect mifepristone. A linear dependence of the peak currents on mifepristone concentrations is observed in the range 4 × 10-7-6 × 10-6mol/L. The relative standard deviation is 4.5% for six successive determinations at 1 × 10-6mol/L solution. The detection limit is 2 × 10-7mol/L.