Neural probes

Intracortical probe arrays – Microelectrodes – 3D- Arrays – Action potentials – Electronic depth control – Electrical stimulation – CMOS- compatibility

Competence

In order to gain a basic understanding of the neuronal function of the brain, it is mandatory to record electrical signals directly from its basic building blocks, i.e. the neurons. This asks for miniaturized electrode arrays enabling the analysis of neuronal signals and the underlying neuronal networks within a 3D brain volume. Preferably, these probe arrays allow to stimulate neural tissue in the electrical, chemical and optical domain as well.

At the Microsystems Materials Laboratory of IMTEK, we develop implantable micro electrode arrays based on silicon using standard CMOS technologies and modified process technologies of IMTEK's clean room. These processes are combined with commercially available IC technologies, e.g. wafer grinding to achieve minimal probe cross-sections. Our process technology is CMOS compatible which makes it possible to realize high-density probe arrays exceeding the current state of the art in probe technology. Beside, our research and development activities aiming for innovative probe arrays and functionalities including chemical intervention using microfluidic channels or optogenetic stimulation using integrated laser diodes, new assembly technologies and instruments for probe insertion are developed and tested by our team. We further work on the long term recording capability of our probe arrays and integrate them into wireless recording systems.

Fields of Application

Basic research in neuroscience

Team

Dr. Patrick Ruther, project leader
Dipl.-Ing. Frederick Pothof, Ph.D. student
M.Sc. Falk Barz, scientific collaborator
Dipl.-Ing. Tobias Holzhammer, scientific collaborator
M.Sc. Michael Schwärzle, Ph.D. student

Projects

Current

BrainLinks-BrainTools projects:

Completed

EU-Projekt NeuroProbes
Dual side probe arrays (Yu- Tao Lee)
Polyimide probe on silicon (Yu-Tao Lee)
Membrane transfer (Diploma thesis Dominik Moser)

Selected publications

K. Seidl, M. Schwaerzle, I. Ulbert, H. P. Neves, O. Paul, P. Ruther
CMOS-Based High-Densitiy Silicon Microprobe Arrays for Electronic Depth Control in Intracortical Neural Recording
2011 J Microelectromech S, volume: 20, pages: 1439 -1448
S. Herwik, O. Paul, P. Ruther
Ultrathin Silicon Chips of Arbitrary Shape by Etching Before Grinding
2011 J Microelectromech S, volume: 20, pages: 791 - 793
S. Herwik, S. Kisban, A.A.A. Aarts, K. Seidl, G. Girardeau, K. Benchenane, M.B. Zugaro, S.I. Wiener, O. Paul, H.P. Neves, P. Ruther
Fabrication technology for silicon-based microprobe arrays used in acute and sub-chronic neural recording
2009 J Micromech Microeng, volume: 19, 074008
P. Ruther, S. Herwik, S. Kisban, K. Seidl, O. Paul
Recent Progress in Neural Probes Using Silicon MEMS Technology
2010 Ieee J Transaction on Electrical and Electronic Engineering, volume: 5, pages: 505 - 515
S. Spieth, O. Brett, K. Seidl, A.A.A. Aarts, M.A. Erismis, S. Herwik, F. Trenkle, S. Tätzner, J. Auber, M. Daub, H.P. Neves, R. Puers, O. Paul, P. Ruther, R. Zengerle
A floating 3D silicon microprobe array for neural drug delivery compatible with electrical recording
2011 J Micromech Microeng, volume: 21, pages: 125001 - 125017
K. Seidl, S. Spieth, S. Herwik, J. Steigert, R. Zengerle, O. Paul. P. Ruther
In-Plane silicon probes for simultaneous neural recording and drug delivery
2010 J. Micromech Microeng 2010, no. 105006, pages: 1 - 11
O. Frey, P.D. van der Wal, S. Spieth, O. Brett, K. Seidl, O. Paul, P. Ruther, R. Zengerle, N.F. de Rooij
Biosensor microprobes with integrated microfluidic channels for bi-directional neurochemical interaction
2011 J Neural Eng, volume: 8, pages: 66001 - 66010

Equipment

NeuroInserter
Impedance spectroscopyr

Partners

Our probe arrays are currently used by various partners from academia and research centers and adapted to different animal models. Among others, we cooperate on the national level with

Charité, Berlin (Dr. C. Gertler)
University of Tuebingen (Dr. P. Cesare, Dr. D. Brugger)
Ernst-Strüngmann-Institute in Frankfurt (Dr. I. Diester)
University of Freiburg (Prof. U. Egert, Prof. Schulze-Bonhage, Prof. C. Weiller)

and internationally with

University of Parma, Italy (Prof. G. Rizzolatti, Prof. L. Fogassi, Prof. L. Bonini, Prof. S. Rozzi)
University of Cambridge, Great Britain (Prof. J. Dalley, Dr. T. Holtzman)
University of Lund, Sweden (Dr. H. Jörntell)
Baylor College of Medicine, Houston, USA (Prof. A. Tolias)

Our standard probe arrays of both the passive and active type as well as CMOS-based arrays for electronic depth control (EDC) are commercialized through Atlas Neuroengineering a joint spin-off company by members of IMTEK and IMEC.

Contact

Dr. Patrick Ruther

Email: ruther@imtek.de

Tel.: +49 (0) 761 203-7197

Fax: +49 (0) 761 203-7192