Non-specific and specific interactions on functionalized polymer surface studied by FT-SPR

▶ A biotinylated polymer, poly(lactide-co-2,2-dihydroxymethyl-propylene carbonate-graft-biotin) [P(LA-co-DHC/biotin)] was synthesized and served as a model polymer, on which co-existed non-specific protein adsorption and specific interaction. ▶ Three different treatment were used to modify the polymer film to let the films had different properties. ▶ A newly developed technology, Fourier transform surface plasmon resonance (FT-SPR) was utilized to study specific and non-specific interactions between proteins and a biotinylated polymer film by monitoring adsorptions of streptavidin (SAv) and bovine serum albumin (BSA) on the polymer films at the same time. ▶ The hydration treatment led to migration of the biotin moieties from inner film to surface and thus resulted in less BSA adsorption and more SAv binding. ▶ Blocking layer on the polymer surface saturated the active sites for physical and chemical adsorptions on the surface and thus the non-specific adsorption of BSA was the weakest, while the specific binding of SAv on the blocked film was relatively the highest.