Deposition of Gold nanoparticles on a chemically modified glass surface due to Immobilization of Biomolecules

Metallic nanoparticles, such as Au and Ag, can be attached to a variety of thiol and amino terminated organosilanes SAMs. This SAMs of bifunctional molecules that cross-link the nanoparticles to the surface can be used to attach biomolecules on surfaces to fabricate kind of biosensor. The results of this study are essential for the development of new classes of nanoparticles functionalized glass surfaces. So a new immobilization method has been used to develop optical enzymatic biosensors. In this study cytochrome c selected as sample protein to immobilization on glass surface. Au nanoparticles were synthesized through sodium citrate reduction of HAuClR4R and sensor chips were fabricated by chemisorption of these nanoparticles on organosilane-functionalized glass that both sides of the glass slide were coated with organosilane then were used as the substrate for colloidal gold layer assembly. After incubation of the glass slide in the gold nanoparticle suspension it was washed gently with ultrapure water. Then the transmission spectrum was measured in a glass cell. A deposited Au nanoparticle was immersed in 0.02 M 3-mercaptopropionic acid aqueous solution for 2 h at room temperature and incubated in cytochrome c solution in the presence of (1-ethyl-3(3-dimethylaminopropyl) carbodiimide methiodide) EDC at 4°C. Deionized water was used in all experiments.

Keywords:

Gold nanoparticle , glass surface , silanization , immobilization