Well Defined Surface Preparation with Phospholipid Polymers for Highly Sensitive Immunoassays

摘要

Plastic substrates were modified with 2-methacryoyloxyethyl phosphorylcholine (MPC) copolymer brushes by surface-initiated atom transfer radical polymerization (ATRP) with a mean chain density of 2.44 chains/nm~2 and a chain length around 50nm. Ellipsometry, X-ray photoelectron spectroscopy, gel permeation chromatography, nuclear magnetic resonance and atomic force microscopy were used to characterize the modified surfaces. MPC was copolymerized with a methacrylate monomer including an active ester unit which can link covalently with antibodies. They latter were immobilized on these well-defined surfaces for characterization and a further use in enzyme-linked immunosorbent assay (ELISA). All kinds of surfaces displayed a good density of immobilized antibodies mainly forming globular packs of around 500 units. A water-soluble MPC polymer-based stabilizer added to the antibody solution could further their individual immobilization.