Surface modification of polyurethane using sulfonated PEG grafted polyrotaxane for improved biocompatibility

Sulfonated poly(ethylene glycol) (PEG-SO3) grafted polyrotaxanes (PRx-PEG-SO3) were prepared in order to utilize the unique properties of PEG-SO3 and the supramolecular structure of PRx, in which PEG-SO3 grafted alpha-cyclodextrins (alpha-CDs) were threaded onto PEG segments in a PEG-b-poly(propylene glycol) (PPG)-b-PEG triblock copolymer (Pluronic) chain capped with bulky end groups. Some of the PRx-PEG-SO3 demonstrated a higher anticoagulant activity in case of PRx-PEG-SO3 (P105), and compared with the control they showed a lower fibrinogen adsorption in PRx-PEG-SO3 (F68) and a higher binding affinity with fibroblast growth factor. The obtained results suggested that polyrotaxane incorporated with PEG-SO3 may be applicable to the surface modification of clinically used polymers, especially for blood/cell compatible medical devices.