Immunoglobulin G immobilization on PVDF surface

Immobilization of antibody molecules onto hydrophobic polymeric surfaces with disordered orientation is something unwanted in many applications. To overcome this drawback, controlled immunoglobulin G (IgG) immobilization onto poly(vinylidene fluoride) surface was investigated in this paper. A two-step process involving radiofrequency plasma pretreatment for polymer surface functionalization, followed by coupling reaction was developed, after which immunoglobulin G was immobilized onto the surface directly or via protein-A. IR and XPS data proved that the process is more efficient when the radiofrequency plasma pretreatment was performed using N-2 and N-2/H-2 as discharge gases. NIR-CI, AFM and XPS surface evaluation revealed that immobilization of IgG onto N-2/H-2 plasma-treated PVDF via grafted protein-A was achieved with an ends-on orientation, leaving available the antigen binding sites of IgG. This procedure could be a promising route for the preparation of oriented IgG assembly onto PVDF, useful in biomedical, membranes or sensors applications. QCM results showed a better antibody antigen interaction when IgG immobilization onto PVDF substrate is mediated by protein A. (C) 2013 Elsevier B.V. All rights reserved.