The use of glass as solid phase in enzyme immunoassay as exemplified by the detection of circulating immune complexes

This article describes a solid-phase enzyme immunoassay for the quantitative determination of circulating immune complexes based on the covalent binding of proteins to glass. A quantitative comparison between adsorption to polystyrene and covalent binding to glass gave a protein higher concentration on the glass support. This leads, in connection with the strong attachment of the protein, to a higher sensitivity and precision in immunoassay. The binding of C1q to glass as solid phase offers the possibility to reuse the protein as well as the glass support after accomplishment of the immunoassay which can reduce the cost of the assay in routine work dramatically. Furthermore, the immobilization of C1q to glass gives an extreme stability of the protein which means that the c1q-coated glass supports can be used up to one year under routine conditions.