Layer by layer assembled phosphorylcholine groups on paclitaxel/chitosan nanofibers coatings for hemocompatibility improvement

Abstract

A novel layer by layer (LbL) assembled structure with phosphorylcholine groups was fabricated to improve the hemocompatibility of paclitaxel/chitosan (PTX/CS) nanofibers (NF) coatings The random copolymers with phosphorylcholine groups poly (2‑methacryloyloxy-ethylphosphorylcholine‑co‑methacrylicacid) (PMAs) were synthesized through free radical polymerization and then first PMA layer formed on PTX/CS NF coatings via electrostatic interactions. After that CS polycation and PMA polyanion thin films LbL formed on PTX/CS NF coatings. The LbL structure was confirmed by X-ray photoelectron spectroscopy (XPS) and water contact angle. The drug release in vitro indicated that the PMA modified PTX/CS NF coatings (PTX/CS-PMA NF coatings) showed a sustained slower release of PTX drug. The LbL coatings containing phosphorylcholine groups could significantly reduce proteins adsorption, platelets adhesion and cell adhesion. They showed a lower platelet (about 6%) and protein (30–40%) (bovine serum albumin, BSA; bovine plasma fibrinogen, Fg) adhesion. Meanwhile, the adhesion of human umbilical vein endothelial cells (HUVECs) was also found reduced. These results demonstrate that the preparation of PMA modified coatings is a simple strategy to improve the hemocompatibility of PTX/CS NF coatings, has good potential for application in blood-contacting materials and devices. Statement of significanceWe develop a simple method to improve the hemocompatibility of paclitaxel/chitosan (PTX/CS) nanofibers (NF) coatings, which can significantly reduce the protein adsorption, and the adhesion of cells and platelets. Using layer by layer (LbL) assembly with PMA polyanion and CS polycation, multilayered PMA/CS films formed on the PTX/CS NF coatings. The X-ray photoelectron spectroscopy (XPS) and water contact angle characterization demonstrated that a cell outer membrane mimetic structure was formed on the PTX/CS NF coatings. The hemocompatibility of modified surface was significantly improved as shown by 94% adhesion suppression for platelets and 60–70% adsorption suppression for bovine plasma fibrinogen (Fg) and bovine serum albumin (BSA). The drug release in vitro indicated that the PMA modified PTX/CS NF (PTX/CS-PMA) coatings had a sustained drug release. Thus this paper provides a facile method for fabricating cell outer membrane mimetic structure which can improve hemocompatibility of blood-contacting material surfaces.