Overview of Technology
Properties of BMSEED’s stretchable microelectrode arrays (sMEAs):
Flexible, Stretchable, and Soft
Recording and Stimulation of Electrophysiological Activity
Mechanically Robust: stretch, bend, twist
How sMEAs work with MEASSuRE:
The cells are stretched by pulling the silicone membrane with the embedded microelectrodes over an indenter. The electrodes stretch with the tissue, thus being able to record neural activity before and after stretching from the same location.
How is this possible?
Microcracked gold films offer a combination of desirable properties:
low electrical impedance
elastically stretchable
low elastic modulus
low fatigue
inexpensive
BMSEED has an exclusive license for all applications (US Patent 7,491,892)
Electron microscopy image of a microcracked gold film.
Why is it important that the gold film is microcracked?
Microcracked gold film on PDMS (sMEAs)
Microcracked gold films can be stretched by over 70% while remaining electrically conductive.
Smooth (no features) gold film on PDMS
Smooth gold films rupture at strains less than 2% and cease to electrically conduct.
Controlling the morphology is therefore very important. To control the morphology of the gold film requires knowledge of the process parameters that affect the morphology:
elastic modulus
pre-treatment of the silicone
film thickness
deposition temperature
adhesion layer