ORIENTED IMMOBILIZATION OF FAB' FRAGMENTS ON SILICA SURFACES

摘要

Fab' fragments of rabbit anti-human IgG were immobilized in oriented form on derivatized silica surfaces containing pyridyl disulfide groups. The fragments were also covalently coupled in random form to glutaraldehyde-bound silanized silica surfaces, The surfaces were characterized by X-ray photoelectron spectroscopy and ellipsometry. Antigen binding activities of the immobilized Fab' fragments were determined by solid-phase enzyme immunoassay. The results showed that the changes in orientation of the immobilized fragments drastically influence the antigen binding activity of the fragments, and the antigen binding activity of the fragments in oriented form is 2.7 times higher than that in random form. Such immobilized fragments could find extensive applicability in the design of immunosensors for monitoring of soluble antigens.