Polymer Hydrogel/Polybutadiene/Iron Oxide Nanoparticle Hybrid Actuators for the Characterization of NiTi Implants

Materials

Aleksandra Jeličić²  Alwin Friedrich²  Katarina Jeremić³  Gerd Siekmeyer¹ 

[1] ADMEDES Schüssler GmbH, D-75179 Pforzheim, Germany;Institute of Chemistry, University of Potsdam, D-14476 Golm, Germany;Faculty of Technology and Metallurgy, University of Belgrade, RS-11120 Beograd, Serbia

关键词: NiTi;    nitinol;    inner surface;    hydrogel;    polybutadiene;    magnetic nanoparticles;   

DOI  :  10.3390/ma2010207

来源: mdpi

【 摘 要 】

One of the main issues with the use of nickel titanium alloy (NiTi) implants in cardiovascular implants (stents) is that these devices must be of very high quality in order to avoid subsequent operations due to failing stents. For small stents with diameters below ca. 2 mm, however, stent characterization is not straightforward. One of the main problems is that there are virtually no methods to characterize the interior of the NiTi tubes used for fabrication of these tiny stents. The current paper reports on a robust hybrid actuator for the characterization of NiTi tubes prior to stent fabrication. The method is based on a polymer/hydrogel/magnetic nanoparticle hybrid material and allows for the determination of the inner diameter at virtually all places in the raw NiTi tubes. Knowledge of the inner structure of the raw NiTi tubes is crucial to avoid regions that are not hollow or regions that are likely to fail due to defects inside the raw tube. The actuator enables close contact of a magnetic polymer film with the inner NiTi tube surface. The magnetic signal can be detected from outside and be used for a direct mapping of the tube interior. As a result, it is possible to detect critical regions prior to expensive and slow stent fabrication processes.

【 授权许可】

CC BY   
© 2009 by the authors; licensee Molecular Diversity Preservation International, Basel, Switzerland.