Adsorption of human serum albumin to polystyrene latex grafted with n,n- dimethylacrylamide

• Main Author: Ramezani, Farhad
• Format: Others
• Language: English
• Published: 2009
• Online Access: http://hdl.handle.net/2429/9253

Biocompatible materials can be defined as materials which can be introduced into a living organism without producing stress or traumatic response. When a solid material comes in contact with a biological medium, a layer of protein immediately binds to the surface. Subsequent defensive responses depend on the type and binding orientation of the protein on the surface. Therefore, primary surface protein binding is directly related to the type of physiological response observed in the body. Surfaces coated with grafted hydrophilic polymers can reduce non-specific protein adsorption. The hydrophilic nature of the grafted chain reduces the hydrophobic driving force. The long grafted chains extending out through the electrical double layer can reduce electrostatic driving forces. Non-specific protein can be excluded by the grafted chains and the solvent trapped between grafted chains. Polymer chains of hydrophilic poly(N,N -dimethylacrylamide) of different lengths were polymerized in situ by initiation from aldehyde groups on the surface of polystyrene latex. Using the techniques of particle electrophoresis, conductometric titration and elemental analysis, the surfaces of these latexes were analyzed. The adsorption isotherms of human serum albumin (HS A) to these latexes were measured. The results indicate that HSA has an affinity for the grafted poly(N,N -dimethylacrylamide). The exclusion effect of the grafted polymer in reducing HSA adsorption was greatest with the medium length grafted chains. The shorter or longer grafted chains on the latex did not reduce HSA adsorption compared with non-grafted latex. === Medicine, Faculty of === Pathology and Laboratory Medicine, Department of === Graduate