L angmuir 1995,11, 2344-2347
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.
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 hydrophilic-except in the
reverse-phase mode-in order to avoid irreversible interactions and protein denaturation. The use ofwater-soluble polymers in the adsorbed coating technology turns out to
be one of the most efficient methods for the hydrophilization of polystyrene-divinylbenzene (PS-DVB) particles. Thus the adsorption of polyelectrolyte onto charged
polystyrene, Le., polystyrene on which ionic groups have
been grafted, leads to highly hydrophilic ion-exchange
materiaL3 Hydrophilization of PS-DVB can also be
achieved by adsorption of nonionic polymers such as e thyl
hydroxyethyl c e l l ~ l o s e poly(ethy1ene oxide)-poly(pro,~,~ pylene oxide) copolymer^,^,^ poly(viny1
polyglycerol.1° However, it is well-known that these
polymers partially desorb when exposed to other polymers
or proteins.11J2 To overcome this problem, low concentra-
* To whom correspondence should be addressed
Abstract published in A dvance A C S Abstracts, J uly 1, 1995. ( l)Moore, J. J . P olym. Sci. 1964,Part 2, 835.
( 2) Lee, D. P. J . C hromatogr. Sci. 1982,20, 03.
(3) R ounds, M. A ,; Regnier, F. E . J . C hromatogr. 1988,4 43, 73. ( 4) M almsten, M.; L indman, B .; Holmberg, K.; B rink, C . L angmuir 1991,7,2412.
(5) Malmsten, M.; Tiberg, F. L angmuir 1993,9 , 1098.
( 6 ) B ridgett, M. J.; D avies, M. C .; D enyer, S. P. B iomaterials 1992, 1 3, 411.
( 7) Lee, J.H.; Kopecekova, P.;Kopecek, J.; ndrade, J.D.Biomaterials A
1990,1 1, 455.
( 8) T uncel, A.; Denizli, A.; Purvis, D .; Lowe, C. R .; Piskin, E . J. Chromatogr. 1993,6 34, 161.
( 9) Leonard, M.; F ournier, C.; Dellacherie, E . J . C hromatogr. 1996, 664,39.
(10) V arady, L.; u, N .; Yang, Y. B .; Cook, S. E .; Afeyan, N .; Regnier, M
F. E.J . Chromatogr. 1993,6 31, 107.
(11)Tiberg, F.;Malmsten, M.; Linse, P.; Lindman, B. L angmuir 1991, 7.2723.
( 12) S tuart C . M . A.; Cosgrove, T .; V incent, B.Adu. Colloid Interface Scz. 1986,24,143.
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