Fabrication of self-expandable NiTi thin film devices with micro-electrode array for bioelectric sensing, stimulation and ablation.
Self-expandable medical devices provide mechanical functionality at a specific location of the human body and are viable for minimal invasive procedures. Besides radiopaque markers and drug-eluting coatings, next generation self-expandable devices can be equipped with additional functionality, such as conductive and flexible electrodes, which enables chronic recording of bioelectrical signals, stimulating or ablating tissue. This promises new therapeutic options in various medical fields, among them in particular neuromodulation (e.g. deep brain stimulation), BioMEMS, radio frequency ablation, mapping or denervation. However, the fabrication of such multi-functional devices is challenging. For this study we have realized a 35 μm thick, superelastic NiTi thin film stent structure with six isolated electrodes on the outer circumference, each electrode connected to a contact pad at the end of the stent structure, using magnetron sputtering, UV lithography and wet chemical etching. Mechanical and electrical properties of the device during typical loading conditions, i.e. crimping, simulated pulsatile and electrochemical testing, were characterized and reveal promising results. For the fabrication of future multifunctional, minimal invasive medical devices, such as electroceuticals or other intelligent implants, NiTi thin film technology is therefore a versatile alternative to conventional fabrication routes.
Acquandas GmbH, Kaiserstrasse 2, 24143, Kiel, Germany. bechtold@acquandas.com.
Christoph
0000-0002-8407-225X
C
Bechtold
Acquandas GmbH, Kaiserstrasse 2, 24143, Kiel, Germany.
Rodrigo Lima
RL
de Miranda
Acquandas GmbH, Kaiserstrasse 2, 24143, Kiel, Germany.|Institute for Materials Science, Faculty of Engineering, University of Kiel, Kaiserstrasse 2, 24143, Kiel, Germany.
Christoph
C
Chluba
Institute for Materials Science, Faculty of Engineering, University of Kiel, Kaiserstrasse 2, 24143, Kiel, Germany.
Eckhard
E
Quandt
D055011:Ablation Techniques / Q000295:instrumentation*; D004553:Electric Conductivity; D004558:Electric Stimulation / Q000295:instrumentation*; D004867:Equipment Design; D055595:Mechanical Phenomena; D008839:Microelectrodes; D009532:Nickel; D014025:Titanium
C040654:titanium nickelide; D009532:Nickel; D014025:Titanium
Bioelectric sensing; Medical devices; Micro electrodes; Nitinol; Shape memory; Stimulation; Superelastic