SU-8-based microneedles for in vitro neural applications

This paper presents novel design, fabrication, packaging and the first in vitro neural activity recordings of SU-8-based microneedles. The polymer SU-8 was chosen because it provides excellent features for the fabrication of flexible and thin probes. A microprobe was designed in order to allow a clean insertion and to minimize the damage caused to neural tissue during in vitro applications. In addition, a tetrode is patterned at the tip of the needle to obtain fine-scale measurements of small neuronal populations within a radius of 100 µm. Impedance characterization of the electrodes has been carried out to demonstrate their viability for neural recording. Finally, probes are inserted into 400 µm thick hippocampal slices, and simultaneous action potentials with peak-to-peak amplitudes of 200–250 µV are detected.

[1]  Rosa Villa,et al.  Manufacturing and full characterization of silicon carbide-based multi-sensor micro-probes for biomedical applications , 2007, Microelectron. J..

[2]  Rosa Villa,et al.  Study of functional viability of SU-8-based microneedles for neural applications , 2009 .

[3]  Ivan Cohen,et al.  Threshold Behavior in the Initiation of Hippocampal Population Bursts , 2006, Neuron.

[4]  Jiping He,et al.  Biocompatible benzocyclobutene-based intracortical neural implant with surface modification , 2005 .

[5]  Rebecca S. Shawgo,et al.  Biocompatibility and biofouling of MEMS drug delivery devices. , 2003, Biomaterials.

[6]  L. Cauller,et al.  Biocompatible SU-8-Based Microprobes for Recording Neural Spike Signals From Regenerated Peripheral Nerve Fibers , 2008, IEEE Sensors Journal.

[7]  G. Gabriel,et al.  Easily made single-walled carbon nanotube surface microelectrodes for neuronal applications. , 2009, Biosensors & bioelectronics.

[8]  G. Gabriel,et al.  SU-8 microprobe with microelectrodes for monitoring electrical impedance in living tissues. , 2009, Biosensors & bioelectronics.

[9]  David C. Martin,et al.  A finite-element model of the mechanical effects of implantable microelectrodes in the cerebral cortex , 2005, Journal of neural engineering.

[10]  P. Vettiger,et al.  High-aspect-ratio, ultrathick, negative-tone near-uv photoresist for MEMS applications , 1997, Proceedings IEEE The Tenth Annual International Workshop on Micro Electro Mechanical Systems. An Investigation of Micro Structures, Sensors, Actuators, Machines and Robots.

[11]  S. Takeuchi,et al.  Fabrication of Flexible Neural Probes With Built-In Microfluidic Channels by Thermal Bonding of Parylene , 2006, Journal of Microelectromechanical Systems.

[12]  P. Renaud,et al.  Flexible polyimide probes with microelectrodes and embedded microfluidic channels for simultaneous drug delivery and multi-channel monitoring of bioelectric activity. , 2004, Biosensors & bioelectronics.

[13]  J. Csicsvari,et al.  Massively parallel recording of unit and local field potentials with silicon-based electrodes. , 2003, Journal of neurophysiology.

[14]  Jiping He,et al.  Polyimide-based intracortical neural implant with improved structural stiffness , 2004 .

[15]  T. Nichols,et al.  Flexible microelectrode arrays with integrated insertion devices , 2001, Technical Digest. MEMS 2001. 14th IEEE International Conference on Micro Electro Mechanical Systems (Cat. No.01CH37090).