Preliminary studies of application of eggshell membrane as immobilization platform in sandwich immunoassay

A novel immunoassay using the eggshell membrane as immobilization platform for determination of human IgG (HIgG) has been developed. The immunoassay was based on a sandwich immunoreaction of rabbit anti-human IgG (primary antibody), HIgG and the goat anti-human IgG labeled with FITC (secondary antibody). Due to well permeability and highly biocompatibility of eggshell membrane, a friendly microenvironment was constructed to prolong the life-times of the immobilized proteins. Under the optimal conditions, the fluorescence intensity is linear to the concentration of HIgG in a range of 20–100 ng mL−1 (r = 0.9918). The proposed method was successfully applied to the determination of the HIgG in the standard blood serum, and the results are satisfactory compared with that obtained by general immunonephelometric method.