Bedair, Tarek M. Cho, Youngjin Joung, Yoon Ki Han, Dong Keun 2024-01-20T08:34:20Z 2024-01-20T08:34:20Z 2021-09-02 2014-10-01 0927-7765 https://pubs.kist.re.kr/handle/201004/126260 Metal-based drug-eluting stents (DESs) have severe drawbacks such as peeling-off and cracking of the coated polymer. To prevent the fracture of polymer-coated layer and improve the durability of DES, poly(L-lactide) (PLLA) brushes were synthesized onto cobalt-chromium (Co-Cr or CC) surface through atom transfer radical polymerization (ATRP) of 2-hydroxyethylmethacrylate (HEMA) followed by surface-initiated ring opening polymerization (SI-ROP) of L-lactide. The polymer brushes were then characterized by attenuated total reflection-Fourier transform infrared (ATR-FTIR), water contact angle, ellipsometry, Xray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), and scanning electron microscopy (SEM). All of the unmodified and modified Co-Cr surfaces were coated with a matrix of poly(D-L-lactide) (PDLLA) and sirolimus (SRL). The in vitro drug release profile was measured for 70 days. The PLLA-modified Co-Cr showed a biphasic release pattern in the initial burst followed by a slow release. On the other hand, the unmodified Co-Cr showed fast drug release and detachment of the coated polymer layer due to the instability of the polymer layer on Co-Cr surface. In comparison, the PLLA-modified Co-Cr preserved a uniform coating without detachment even after 6 weeks of degradation test. The platelet morphology and low density of platelet adhered on the modified layer and the SRL-in-PDLLA coated Co-Cr surfaces demonstrated that these samples would be blood compatible. Therefore, the introduction of PLLA brush onto Co-Cr surface is proved to dramatically improve the durability of the coating layer, and it is a promising strategy to prevent the coating defects found in DESs. (c) 2014 Elsevier B.V. All rights reserved. English ELSEVIER SCIENCE BV DRUG-ELUTING STENTS BALLOON-EXPANDABLE-STENT CORONARY-ARTERY-DISEASE TITANIUM PROLIFERATION IMPLANTATION THROMBOSIS THROMBOGENICITY ANGIOPLASTY MONOLAYERS Biodegradable polymer brush as nanocoupled interface for improving the durability of polymer coating on metal surface Article 10.1016/j.colsurfb.2014.08.025 1 COLLOIDS AND SURFACES B-BIOINTERFACES, v.122, pp.808 - 817 COLLOIDS AND SURFACES B-BIOINTERFACES 122 808 817 scie scopus 000343612900101 2-s2.0-84909946071 Biophysics Chemistry, Physical Materials Science, Biomaterials Biophysics Chemistry Materials Science Article DRUG-ELUTING STENTS BALLOON-EXPANDABLE-STENT CORONARY-ARTERY-DISEASE TITANIUM PROLIFERATION IMPLANTATION THROMBOSIS THROMBOGENICITY ANGIOPLASTY MONOLAYERS Drug-eluting stent Poly(L-lactide) brush Atom transfer radical polymerization Ring opening polymerization Drug release