Sustained drug release using cobalt oxide nanowires for the preparation of polymer-free drug-eluting stents.

Abstract

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 µm. 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.

• Authors: Tarek M Bedair, Il Jae Min, Wooram Park, Yoon Ki Joung, Dong Keun Han
• Journal: Journal of biomaterials applications (J Biomater Appl) Vol. 33 Issue 3 Pg. 352-362 (09 2018) ISSN: 1530-8022 [Electronic] England
• PMID: 30223735 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Alloys
• Anti-Infective Agents
• Delayed-Action Preparations
• Oxides
• Chromium
• Cobalt
• cobalt oxide
• Sirolimus

Topics

• Alloys (chemistry)
• Anti-Infective Agents (administration & dosage, chemistry)
• Chromium (chemistry)
• Cobalt (chemistry)
• Delayed-Action Preparations (chemistry)
• Drug Liberation
• Drug-Eluting Stents
• Nanowires (chemistry, ultrastructure)
• Oxides (chemistry)
• Sirolimus (administration & dosage, chemistry)