Nanostructured stainless steel surfaces by PBII
Human blood vessels sometimes become occluded or weakened. For example, the vessels can be occluded by a tumour, covered with a plaque, or weakened by an aneurysm. Such a vessel can be either reopened, reinforced, or even replaced with a medical endoprosthesis (stents or stent-grafts). For bare metal stents the in-stent restenosis was a serious problem for a number of patients. This spurred the medical device companies to search for an effective way of preventing restenosis. In late 1990’s the first drug eluting stents (DES) were developed as a solution to the problem.
A multilayer pore system on a metal stent’s surface may serve as a platform for the next generation of metal-based drug-eluting stents.
Advantages of the multilayer pore structure:
- Enables storage of therapeutic agents or drugs
- Possesses high biocompatibility
- Provides a basis for other coatings or bio-layers
SEM image of PBII-processed metal surface showing islets and hillocks whose formation depends strongly on implantation temperature. Increasing ion fluence produces a porous layer in addition to the islet/hillock features.