Abstract:

The hydroxyl end groups of a comb-like poly(ethylene glycol) were transformed into aldehyde groups, which were further grafted onto PET substrate. Ligands including lysine and RGD peptide were tethered onto the reactive PEG end groups. Linear PEGs with different molecule weights(Mw=4 000 and 10 000) were also investigated as controls. The surface grafting process was characterized by means of FTIR, ¹ H NMR, contact angle and XPS. The two systems were compared with regarding their abilities to prevent non-specific interaction and to promote cyto-compatibility. Owing to its high branched-arm structure, the comb-like PEG modified surface achieved stronger entropic repulsion than the linear PEG. Meanwhile, more ligands were tethered onto the comb-like PEG modified surface with a great amount of reactive end groups, which increased cell proliferation. The glycocalyx mimicking surface designed with comb-shaped PEG end-tethered by RGD peptide was proved to present non-specific resistance and excellent cyto-compatibility simultaneously.

Key words: Poly(ethylene glycol); Comb-shaped polymer; Aldehyde group; Endothelial cell