Determination of h-Immunoglobulin G by Gold Electrode Modified with Complex of Ni(Ⅱ) and Au Nanoparticles

Unmarked Impedance Type immunoglobulin G (h-IgG) immuno bio-sensor was prepared by self-assembly of L-cysteine, glutaraldehyde, Anti-IgG and h-IgG on the surface of bare gold electrode, and Au nanoparticles modified with complex of Ni(Ⅱ) and thiol-schiff base was prepared and used as electrochemical probe. The surface of the electrode was characterized and the content of h-IgG was determined by AC impedance method. Linear relationship between value of impedance and mass concentration of h-IgG was kept in the range of 10-100 μg·L-1, with detection limit (3s/k) of 4.54×10-7g·L-1. Value of RSD (n=10) found with a same modified electrode in 10 successive determinations of h-IgG solution was 0.55%.