An amperometric biosensor for glucose based on self-assembling nanoparticles and electrosynthesis of poly-o-diaminobenzene on the Prussian blue-modified gold electrode

A novel glucose biosensor fabricated by self-assembling polymer of Prussian blue and 1,2-diaminobenzenes (1,2-DAB), gold nanoparticles and glucose oxidase (GOD) has been studied on gold substrate. A clean gold electrode was first immersed in solution to produce a self-assembled layer of PB, then electrosynthesis of poly-1,2-diaminobenzene on the surface of Prussian blue-modified electrode, and then the gold nonoparticles were chemisorbed onto the free amines of the poly 1,2-diaminobenzenesm; finally, GOD was adsorbed onto the surface of the gold nanoparticles. The modified process was characterized by cyclic voltammetry (CV). Analytical parameters such as pH, temperature were also studied. The electrode displayed excellent electrocatalytical response to the glucose. The peak currents were proportional to the glucose concentration in the range of 2.0 x 10(-6) to 6.0 x 10(-3) M with a correlation coefficient of 0.9939. Moreover, such a modified electrode exhibits a good stability and sensitivity.