Protein‐rejecting ability of surface‐bound dextran in end‐on and side‐on configurations: Comparison to PEG

Abstract

There is much interest in attaching polyethylene glycol (PEG) and other hydrophilic, neutral polymers to surfaces to reduce the extent of protein and cell adsorption. Interestingly, these same surface-bound polymers are effective in masking surface charge and reducing electrokinetic effects such as particle electrophoretic mobility, streaming potential, and electroosmosis. It is apparent that similar molecular properties are responsible for both protein and cell rejection and reduction of electrokinetic effects. In this work we compared the fibrinogen-rejecting ability and the effect on electrophoretic mobility of three polymer coatings bound to polystyrene. The three polymers were side-bound dextran, end-bound dextran, and end-bound PEG. The results of these measurements were used to elucidate the importance of polymer packing density and polymer layer thickness on protein adsorption and reduction of electrokinetic effects. Protein adsorption appears not to be sensitive to polymer layer thickness or the presence of dilute polymer tails in a surface coating, while electrokinetic effects are. Protein adsorption is, however, very sensitive to the availability of exposed surface. Finally, the unique effectiveness of PEG is apparent in this research as in previous studies.

Proteins at Interfaces

“…These properties allow steric repulsion interactions to dominate over van der Waals attraction. There is no general agreement on the optimal structure of such a surface, but the important variables are believed to be the PEO chain length and spacing on the surface (8,9). In the present volume the paper by McPherson, Lee and Park shows that PEO chains of length 3 to 128 immobilized on glass (through the use of PEO-PPO-PEO block copolymers) are effective in reducing the adsorption of fibrinogen and lysozyme.…”

Enhanced Antifouling Properties of Carbohydrate Coated Poly(ether sulfone) Membranes

“…19 Importantly, glycosylated surfaces have attracted much attention as platforms for investigating the mechanisms involved in nonspecific adsorption of proteins onto solid surfaces and as a biomimetic strategy for minimizing fouling in aqueous media. 20,21 Surface coatings consisting of high molecular weight polysaccharides such as dextran have been shown to reduce protein or cell adhesion to surfaces, 22,23 while modifications with short oligosaccharides or monosaccharides have also been demonstrated to have a pronounced effect on minimizing unspecific protein adsorption and biomass accumulation. [24][25][26][27] Previous work from our group showed that Galactose-modified carbon surfaces obtained via spontaneous grafting of aryldiazonium salts display an increased resistance to Bovine Serum Albumin (BSA) adsorption, compared to bare carbon surfaces.…”

Designing polyethylene glycol (PEG) – plasticized membranes of poly(vinyl alcohol-g-methyl methacrylate) and investigation of water sorption and blood compatibility behaviors

“…The PEG and its derivatives show numerous applications in controlled drug delivery systems, enzyme immobilization matrices to size selective biomembranes, and wound dressings [6]. The PEG gels are used as optical biosensors, drug delivery, patterned hydrogel micro structures, and as substrate materials for directed cell growth [7][8][9][10][11][12].…”