Nanoparticle-mediated bio-sensing promoted the development of novel sensors in the front of medical diagnosis. In the present study, we have generated and examined the potential of titanium dioxide (TiO 2) crystalline nanoparticles with aluminium interdigitated electrode biosensor to specifically detect single-stranded E.coli O157:H7 DNA. The performance of this novel DNA biosensor was measured the electrical current response using a picoam-meter. The sensor surface was chemically functionalized with (3-aminopropyl) triethoxysi-lane (APTES) to provide contact between the organic and inorganic surfaces of a single-stranded DNA probe and TiO 2 nanoparticles while maintaining the sensing system’s physi-cal characteristics. The complement of the target DNA of E. coli O157:H7 to the carboxyl-ate-probe DNA could be translated into electrical signals and confirmed by the increased conductivity in the current-to-voltage curves. The specificity experiments indicate that the biosensor can discriminate between the complementary sequences from the base-mis-matched and the non-complementary sequences. After duplex formation, the complemen-tary target sequence can be quantified over a wide range with a detection limit of 1.0 x 10 -13 M. With target DNA from the lysed E. coli O157:H7, we could attain similar sensitivity. Sta-bility of DNA immobilized surface was calculated with the relative standard deviation (4.6%), displayed the retaining with 99% of its original response current until 6 months. This high-performance interdigitated DNA biosensor with high sensitivity, stability and non-foul-ing on a novel sensing platform is suitable for a wide range of biomolecular interactive analyses.
