ABSTRACT
Polymer coating produces a new surface on the original surface of the material. The surface properties and structure change by this modification. That is, if the layer produced on the surface by the modification is thick enough, the surface shows the properties of the polymer layer used to coat. It is well known that PEGylation, i.e., modification with poly(ethyleneglycol), makes various polymer surfaces more hydrophilic [1, 2]. Therefore, PEGylation using block copolymer, by surface immobilization or other methods, has been reported to reduce the levels of cell adhesion and protein adsorption, the effects of which have been applied to stealth liposomes and microspheres in the field of drug delivery systems. Such changes in surface properties are especially observed in charge density originating from various groups fixed in the surface area and in surface softness, which can be predicted by electrokinetic measurements on polymer particles and from analysis of the data [3, 4].
