A novel strategy for synthesis of hollow gold nanosphere and its application in electrogenerated chemiluminescence glucose biosensor

Well-distributed hollow gold nanospheres (Au-shell@GOD) (20 + 5 nm) were synthesized using the glucose oxidase (GOD) cross-linked with glutaraldehyde as a template. A glucose biosensor was prepared based on Au-shell@GOD nanospheres for catalyzing luminol electrogenerated chemiluminescence (ECL). Firstly, chitosan was modified in a glassy carbon electrode which offered an interface of abundant amino-groups to assemble Au-shell@GOD nanospheres. Then, glucose oxidase was adsorbed on the surface of Au-shell@GOD nanospheres via binding interactions between Au-shell and amino groups of GOD to construct a glucose biosensor. The Au-shell@GOD nanospheres were investigated with TEM and UV-vis. The ECL behaviors of the biosensor were also investigated. Results showed that, the obtained Au-shell@GOD nanospheres exhibited excellent catalytic effect towards the ECL of luminol-H2O2 system. The response of the prepared biosensor to glucose was linear with the glucose concentration in the range of 1.0 mu M to 43 mM (R=0.9923) with a detection limit of 0.31 mu M (signal to noise = 3). This ECL biosensor exhibited short response time and excellent stability for glucose. At the same time the prepared ECL biosensor showed good reproducibility, sensitivity and selectivity. (C) 2014 Elsevier B.V. All rights reserved.