Cytocompatibility of polymers grafted by activated carbon nano-particles

Carbon nano-structures find their application in bio-medicine. In this work we functionalized carbon nano-particles (CNPs) with nitrogen (amine) groups. The CNPs were then chemically grafted onto the surface of polyethyleneterephthalate (PET) and high density polyethylene (HDPE) previously treated (activated) in argon plasma. Transmission electron microscopy (TEM) was used for investigation of the size and form of reactivated CNPs. Chemical composition of the modified polymer surfaces was determined by Raman and X-ray photoelectron (XPS) spectroscopies and by an electrokinetic analysis (zeta potential) as well. Surface contact angle was measured by goniometry. Surface roughness and morphology of polymers grafted with CNPs was studied using atomic force microscopy (AFM). Adhesion and proliferation of vascular smooth muscle cells (VSMC) on CNPs grafted HDPE and PET surfaces were studied in vitro. TEM results show that CNPs aggregate in water solution. Successful grafting of CNPs on the HDPE and PET surfaces was proved by XPS and Raman spectroscopies (amorphous carbon in the form of sp2 hybridization) and by AFM. CNPs grafting of polymer surfaces leads to a decrease of contact angle and also to a change in surface zeta potential. Grafting with CNPs has a positive effect on adhesion and proliferation of VSMC on polymers' surface.