Fabrication of streptavidin functionalized silver nanoparticle decorated graphene and its application in disposable electrochemical sensor for immunoglobulin E

In this report, Ag nanoparticles/graphene hybrid (AgNPs/graphene) was fabricated according to a self-assembly procedure followed by functionalization with streptavidin (SA) and was used as electrochemical label in the electrochemical detection of human immunoglobulin E (IgE) through a sandwich-type strategy. The thiol-capped IgE DNA aptamer was used as capture probe, while the SA functionalized AgNPs/graphene (SA-AgNPs/graphene) linked with biotinylated goat anti-human IgE antibody was used as detection probe. The electrochemical signal from AgNPs anchored on the graphene was obtained through square wave anodic stripping voltammetry. The results demonstrated that this electrochemical biosensor possessed a dynamic range from 10 to 1000 ng mL(-1) with a low detection limit of 3.6 ng mL(-1). (c) 2013 Elsevier B.V. All rights reserved.