Bedair, Tarek M. Min, Il Jae Park, Wooram Joung, Yoon Ki Han, Dong Keun 2024-01-19T22:01:08Z 2024-01-19T22:01:08Z 2022-01-10 2018-09 0885-3282 https://pubs.kist.re.kr/handle/201004/120947 Polymer-based drug-eluting stents (DESs) represented attractive application for the treatment of cardiovascular diseases; however, polymer coating has caused serious adverse responses to tissues such as chronic inflammation due to acidic by-products. Therefore, polymer-free DESs have recently emerged as promising candidates for the treatment; however, burst release of drug(s) from the surface limited its applications. In this study, we focused on delivery of therapeutic drug from polymer-free (or -less) DESs through surface modification using cobalt oxide nanowires (Co3O4 NWs) to improve and control the drug release. The results demonstrated that Co3O4 NWs could be simply fabricated on cobalt-chromium substrate by ammonia-evaporation-induced method. The Co3O4 NWs were uniformly arrayed with diameters of 50-100 nm and lengths of 10 mu m. It was found that Co3O4 NWs were comparatively stable without any delamination or change of the morphology under in vitro long-term stability using circulating system. Sirolimus was used as a model drug for studying in vitro release behavior under physiological conditions. The sirolimus release behavior from flat cobalt-chromium showed an initial burst (over 90%) after one day. On the other hand, Co3O4 NWs presented a sustained sirolimus release rate for up to seven days. Similarly, the polymer-less specimens on Co3O4 NWs substrates sustained sirolimus release for a longer-period of time when compared to flat Co-Cr substrates. In summary, the current approach of using Co3O4 NWs-based substrates might have a great potential to sustain drug release for drug-eluting implants and medical devices including stents. English SAGE PUBLICATIONS LTD CHROMIUM ALLOY SURFACES INTERFACIAL ADHESION PACLITAXEL DELIVERY METAL-SURFACE SIROLIMUS IMPLANTATION RESTENOSIS NANOCOMPOSITE PROLIFERATION HYPERPLASIA Sustained drug release using cobalt oxide nanowires for the preparation of polymer-free drug-eluting stents Article 10.1177/0885328218792141 1 JOURNAL OF BIOMATERIALS APPLICATIONS, v.33, no.3, pp.352 - 362 JOURNAL OF BIOMATERIALS APPLICATIONS 33 3 352 362 scie scopus 000444975600003 2-s2.0-85053674231 Engineering, Biomedical Materials Science, Biomaterials Engineering Materials Science Article CHROMIUM ALLOY SURFACES INTERFACIAL ADHESION PACLITAXEL DELIVERY METAL-SURFACE SIROLIMUS IMPLANTATION RESTENOSIS NANOCOMPOSITE PROLIFERATION HYPERPLASIA Drug-eluting stents cobalt oxide nanowires sustained release polymer-free coating long-term stability sirolimus