A NOVEL BIOSENSOR OF DNA IMMOBILIZATION ON NANO-GOLD MODIFIED ITO FOR THE DETERMINATION OF MIFEPRISTONE

Abstract

A novel DNA modified indium tin oxide (ITO) electrode has been prepared. (3-Aminopropyl)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.

Keywords:

• Biosensor
• DNA-modified electrode
• Au colloid
• Mifepristone

ACKNOWLEDGMENT

This project is supported by National Natural Science of China Foundation (NO. 50072006 and NO.29835110). It is also supported by Doctoral Fund of Ministry of Education of China.