Suppression of Cell and Platelet Adhesion to Star‐Shaped 8‐Armed Poly(ethylene glycol)‐Poly( L ‐lactide) Block Copolymer Films

Summary: To explore the potential of a star‐shaped 8‐armed poly(ethylene glycol)35K‐ block ‐poly( L ‐lactide)37K (8‐armed PEG35K‐ b ‐PLLA37K: $\overline M _{\rm n}$ of PEG = 35 000, $\overline M _{\rm n}$ of PLLA = 37 000) film as a novel bioabsorbable adhesion‐prevention membrane, the water structure, surface contact angle, protein adsorption, and cell and platelet anti‐adhesion properties of such a hydrated film are investigated. Based on the results, it is found that the 8‐armed PEG35K‐ b ‐PLLA37K film exhibits a biologically inert surface, which is the result of a large number of PEG chains and a free water layer on the film surface. This leads to a reduction in protein absorption and cell and platelet adhesion onto the film surface. This implies that the star‐shaped 8‐armed PEG35K‐ b ‐PLLA37K film can be utilized as a novel bioabsorbable adhesion‐prevention membrane.A schematic presentation of the protein adsorption, platelet adhesion, and cell attachment phenomena for the 8‐armed PEG‐ b ‐PLLA films.