Electrochemiluminescence Immunosensor Based on Carbon Nanotubes and Liposomes for Detection of Human Immunoglobin G
A simple and sensitive electrochemiluminescence(ECL) immunosensor was fabricated by immobilizing goat-anti-human immunoglobulin G (hIgG) antibody on a multi-walled carbon nanotubes (MWCNTs) modified glassy carbon electrode. The hIgG antigen and antibody-tagged liposome can be sequentially bound on the immunosensor through antigen-antibody specific interaction, forming a sandwich-type immunocomplex. The ECL intensity of the immunosensor increased linearly with the hIgG concentration from 0.01 to 0.8 mu g/L with a detection limit of 0.004 mu g/L(S/N = 3). The immunosensor mentioned above was successfully applied for the detection of hIgG in human serum.