Abstract: Combination device containing drug release and HUVECs selectivity were constructed based on PEG copolymer. Polyethylene glycol methacrylate(PEGMA)-butyl methacrylate(BMA)(PEGB) loading rapamycin was cast onto polyethylene terephthalate(PET) substrate as base layer, and then PEGMA-BMA-p-nitrophenyloxycarbonyl polyethylene glycol methacrylate(MEONP)(PEGBN) conjugated REDV peptide was further coated as top layer. In vitro profile of drug release indicates that rapamycin keeps a slow and sustain release implying that the top layer acts as a diffusion barrier. Cell behavior indicates that rapamycin remains its activity in inhibiting human umbilical vein endothelial cells(HUVECs) and human aortic smooth muscle cells(HASMCs) adhesion and proliferation. Although the eluted concentration of rapamycin decreased with drug eluting time, the polymeric coating keeps resisting nonspecific adsorption of HASMCs while REDV enhances HUVECs attachment specifically. This polymeric film with top layer promotes HUVECs competitive adhesion comparing with HASMCs. The immobilization of REDV onto rapamycin loaded PEG matrix could be an effective method to keep sustained inhibition of HASMCs and promote HUVECs competitive adhesion simultaneously.

Key words: Rapamycin, Drug release, Cell selectivity, Endothelialization