Highly sensitive glucose biosensor based on the effective immobilization of glucose oxidase/carbon-nanotube and gold nanoparticle in nafion film and peroxyoxalate chemiluminescence reaction of a new fluorophore

A novel glucose biosensor based on the chemiluminescence (CL) detection of enzymatically generated H2O2 was constructed by the effective immobilization of glucose oxidase (GOD)/carbon-nanotubes (CNTs)/gold nanoparticles (GNPs) in nafion film on graphite support. The influences of various experimental parameters such as solution pH, the action time of the enzyme, interferents and the concentration of CL reagents were investigated. Carbon nanotubes and gold nanoparticles offer excellent catalytic activity toward hydrogen peroxide generation in enzymatic reaction between glucose oxidase and glucose, which would enable sensitive determination of glucose. Under the optimum condition, the linear response range of glucose was found to be 2.25 x 10(-6) to 1.75 x 10(-4) mol L-1, and the detection limit (defined as the concentration that could be detected at the signal-to-noise ratio of 3) was 1.00 x 10(-6) mol L-1. The CL biosensor exhibited good storage stability, i.e., 80% of its initial response was retained after 10 days storage at pH 7.0. The present CL biosensor has been used to determine the glucose concentrations in real serum and urine samples with satisfactory results. (C) 2011 Elsevier B.V. All rights reserved.