1 Department of Biomedical Science, CHA University, Pangyo-ro, Bundang-gu, Seongnam-si, Gyeonggi, Republic of Korea.
2 Chemistry Department, Faculty of Science, Minia University, El-Minia, Egypt.
J Biomater Appl. 2018 Sep;33(3):352-362. doi: 10.1177/0885328218792141.
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 (CoO NWs) to improve and control the drug release. The results demonstrated that CoO NWs could be simply fabricated on cobalt-chromium substrate by ammonia-evaporation-induced method. The CoO NWs were uniformly arrayed with diameters of 50-100 nm and lengths of 10 µm. It was found that CoO 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, CoO NWs presented a sustained sirolimus release rate for up to seven days. Similarly, the polymer-less specimens on CoO 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 CoO NWs-based substrates might have a great potential to sustain drug release for drug-eluting implants and medical devices including stents.
基于聚合物的药物洗脱支架（DES）在心血管疾病的治疗中具有吸引力的应用；然而，由于酸性副产物，聚合物涂层对组织（如慢性炎症）造成了严重的不良反应。因此，无聚合物 DES 最近作为治疗的有前途的候选者出现；然而，药物从表面的爆发释放限制了其应用。在这项研究中，我们专注于通过使用氧化钴纳米线（CoO NWs）进行表面改性来从无聚合物（或更少聚合物）DES 中递送电疗药物，以改善和控制药物释放。结果表明，CoO NWs 可以通过氨蒸发诱导法在钴铬基底上简单地制造。CoO NWs 均匀排列，直径为 50-100nm，长度为 10µm。发现在体外长期稳定性循环系统中，CoO NWs 没有分层或形态变化，比较稳定。西罗莫司被用作在生理条件下研究体外释放行为的模型药物。钴铬平面的西罗莫司释放行为在一天后显示出初始突释（超过 90%）。另一方面，CoO NWs 呈现出长达七天的西罗莫司持续释放率。同样，与钴铬平面相比，CoO NWs 基底上的无聚合物样品表现出更长时间的西罗莫司持续释放。总之，使用 CoO NWs 基底物的当前方法可能具有很大的潜力，可以为药物洗脱植入物和包括支架在内的医疗设备持续释放药物。
