Bedair, Tarek M. Yu, Seung Jung Im, Sung Gap Park, Bang Ju Joung, Yoon Ki Han, Dong Keun 2024-01-20T05:31:04Z 2024-01-20T05:31:04Z 2021-09-03 2015-12-15 0021-9797 https://pubs.kist.re.kr/handle/201004/124624 Drug-eluting stents (DESs) have been used to treat coronary artery diseases by placing in the arteries. However, current DESs still suffer from polymer coating defects such as delamination and peeling-off that follows stent deployment. Such coating defects could increase the roughness of DES and might act as a source of late or very late thrombosis and might increase the incident of restenosis. In this regard, we modified the cobalt-chromium (Co-Cr) alloy surface with hydrophilic poly(2-hydroxyethyl methacrylate) (PHEMA) or hydrophobic poly(2-hydroxyethyl methacrylate)-grafted-poly(caprolactone) (PHEMA-g-PCL) brushes. The resulting surfaces were biocompatible and biodegradable, which could act as anchoring layer for the drug-in-polymer matrix coating. The two modifications were characterized by ATR-FTIR, XPS, water contact angle measurements, SEM and AFM. On the control and modified Co-Cr samples, a sirolimus (SRL)-containing poly(D,L-lactide) (PDLLA) were ultrasonically spray-coated, and the drug release was examined for 8 weeks under physiological conditions. The results demonstrated that PHEMA as a primer coating improved the coating stability and degradation morphology, and drug release profile for short-term as compared to control Co-Cr, but fails after 7 weeks in physiological buffer. On the other hand, the hydrophobic PHEMA-g-PCL brushes not only enhanced the stability and degradation morphology of the PDLLA coating layer, but also sustained SRL release for long-term. At 8-week of release test, the surface morphologies and release profiles of coated PDLLA layers verified the beneficial effect of hydrophobic PCL brushes as well as their thickness on coating stability. Our study concludes that 200 nm thickness of PHEMA-g-PCL as interfacial layer affects the stability and degradation morphology of the biodegradable coating intensively to be applied for various biodegradable-based DESs. (C) 2015 Elsevier Inc. All rights reserved. English ACADEMIC PRESS INC ELSEVIER SCIENCE CHEMICAL-VAPOR-DEPOSITION IN-VITRO DEGRADATION POLY(2-HYDROXYETHYL METHACRYLATE) SURFACE TITANIUM THROMBOGENICITY IMPLANTATION DURABILITY MONOLAYERS STABILITY Effects of interfacial layer wettability and thickness on the coating morphology and sirolimus release for drug-eluting stent Article 10.1016/j.jcis.2015.08.051 1 JOURNAL OF COLLOID AND INTERFACE SCIENCE, v.460, pp.189 - 199 JOURNAL OF COLLOID AND INTERFACE SCIENCE 460 189 199 scie scopus 000363077800023 2-s2.0-84940048168 Chemistry, Physical Chemistry Article CHEMICAL-VAPOR-DEPOSITION IN-VITRO DEGRADATION POLY(2-HYDROXYETHYL METHACRYLATE) SURFACE TITANIUM THROMBOGENICITY IMPLANTATION DURABILITY MONOLAYERS STABILITY Drug-eluting stent Biodegradable polymer Ring-opening polymerization Photo-initiated chemical vapor deposition Polymer brush