SURFACE MODIFICATIONS TO INFLUENCE ADHESION OF BIOLOGICAL CELLS AND ADSORPTION OF GLOBULAR PROTEINS

摘要

It is desired to immobilize intact biological cells or protein molecules at surfaces for enzymes or cells in bioreactors and biosensors, immuno-proteins in solid-state diagnostics and proteinaceous farmacons in drug delivery systems. In other cases immobilization of cells and proteins should be avoided. A generic approach to influence the interaction between a particle (e.g. a cell or a globular protein molecule) and a sorbent surface is to manipulate both long- and short-range forces by grafting soluble polymers or oligomers onto the sorbent surface. Oligomers of ethylene oxide (EO) prevents the particle from making intimate contact with the surface so enzymes may retain their native structure and their enzymatic activity. Another interesting example is the steering effect of pre-adsorbed polymers of EO (PEO) on the orientation of subsequently adsorbing IgG molecules. Most recent research on modifying surfaces by grafting soluble polymers aims at the prevention of protein adsorption and/or adhesion of biological cells. The efficacy of grafted PEO layers to reduce protein adsorption and microbial adhesion will be illustrated for blood plasma proteins, saliva proteins and a number of bacterial and yeast cells.