Dextran
L angmuir 1995,11, 2344-2347
2344
Coating Polystyrene Particles by Adsorption of
Hydrophobically Modified Dextran
C . Fournier, M. Leonard,* I. Le Coq-Leonard, and E . Dellacherie
L CPM, URA C NRS 494, ENSIC B.P. 4 51, 54001 Nancy, France
Received March 14, 1995. I n Final Form: May 22, 1995@
I n order to decrease their hydrophobicity and thus t o reduce the protein adsorption at their surface, polystyrene-divinylbenzene (PS-DVB) particles have been coated with dextran. To favor its adsorption, the polysaccharide was previously substituted with low concentrations of phenoxy groups. The amount of dextran adsorbed onto the PS-DVB surface was examined as a function of the polymer concentration, and various samples of beads, differing in surface dextran concentration, were prepared. The adsorbed polymeric layer was then chemically cross-linked and its stability was checked in the presence of sodium dodecyl sulfate. The hydrophiliccharacter of the various resulting beads was evaluated toward the adsorption ofbovine serum albumin, a stronglyhydrophobic protein. By this study, the conditionsfor coating polystyrene particles were optimized and the dextran layer was shown t o greatly reduce the nonspecific adsorption of proteins.
I. Introduction
Polymer adsorption a t solid-liquid interfaces is a widely studied phenomenon as connected with many important processes including colloidal stabilization, flocculation, adhesion, or coating.
T he reduction of protein adsorption by coating hydrophobic surfaces is of significant importance for many biomedical and biotechnological applications. Particularly, there is a n increasing interest in the use of polystyrene particles for liquid chromatography of biological molecules. These materials exhibit excellent mechanical properties and a good chemical stability over a large range of pH.IJ However, to use this packing material for the chromatography of proteins, it is essential to make the bead surface
2344
Coating Polystyrene Particles by Adsorption of
Hydrophobically Modified Dextran
C . Fournier, M. Leonard,* I. Le Coq-Leonard, and E . Dellacherie
L CPM, URA C NRS 494, ENSIC B.P. 4 51, 54001 Nancy, France
Received March 14, 1995. I n Final Form: May 22, 1995@
I n order to decrease their hydrophobicity and thus t o reduce the protein adsorption at their surface, polystyrene-divinylbenzene (PS-DVB) particles have been coated with dextran. To favor its adsorption, the polysaccharide was previously substituted with low concentrations of phenoxy groups. The amount of dextran adsorbed onto the PS-DVB surface was examined as a function of the polymer concentration, and various samples of beads, differing in surface dextran concentration, were prepared. The adsorbed polymeric layer was then chemically cross-linked and its stability was checked in the presence of sodium dodecyl sulfate. The hydrophiliccharacter of the various resulting beads was evaluated toward the adsorption ofbovine serum albumin, a stronglyhydrophobic protein. By this study, the conditionsfor coating polystyrene particles were optimized and the dextran layer was shown t o greatly reduce the nonspecific adsorption of proteins.
I. Introduction
Polymer adsorption a t solid-liquid interfaces is a widely studied phenomenon as connected with many important processes including colloidal stabilization, flocculation, adhesion, or coating.
T he reduction of protein adsorption by coating hydrophobic surfaces is of significant importance for many biomedical and biotechnological applications. Particularly, there is a n increasing interest in the use of polystyrene particles for liquid chromatography of biological molecules. These materials exhibit excellent mechanical properties and a good chemical stability over a large range of pH.IJ However, to use this packing material for the chromatography of proteins, it is essential to make the bead surface