Thumbtack Multielectrode Array

These chronically implantable Multielectrode Arrays are linear probes having multiple recording sites with a choice of 4, 8, 16, 24 and 32 electrode channels. Electrode sites are numbered from connector to tip. These Thumbtack Multielectrode Arrays are expertly handcrafted and made to order with many finished options available.

The platinum/iridium recording sites are available in 15, 20, 25 and 40 µm diameter options. It is effective for both field potential and single-unit recordings. The precise linear arrangement of the electrode sites enables current source density analysis of the field potential signals as recorded from laminar neural structures. The inter-electrode spacing can be 50, 75, 100, 150 or 200 µm along the length of the probe.

A thin, circular silicone sheet is attached at the top of the microelectrode, perpendicular to the axis of the probe, to hold the Steel Shaft Thumbtack Probe in place, while surface tension between the silicone sheet and the cortical surface assists in securing the probe in position. Output leads are bent at 90° at the top part of the anchoring sheet, and are then embedded in a 10 cm silicone cable/tube which terminates in an Omnetics connector.

Connector interface: 24 channel, 36-pin Omnetics connector with 0.025″ pitch (CON/32m-V). Also available in Nickel-free for MRI-compatibility

Neural probe diameters vary from 185 to 360 µm based on the number of electrodes and the PtIr wire diameter.

The 15 µm electrode site diameter enables effective single-unit recording coupled with low impedance for a better signal-to- noise ratio. Larger diameter recording sites are more suitable for field potential recording.

The most commonly used thumbtack probes are designed to span cortical layers running parallel to the surface of the brain. To record from deeper structures the probes can be made with longer shaft and sites starting not from next to the silicone disc, but further on.

Tip of the probe is according to customer requirement. It may also be possible to manufacture these probes beyond the listed parameters to facilitate the most ideal setup for your research needs.

Lead time: 4-6 weeks

If you would like to learn more about our Thumbtack Probe, we invite you to contact a Plexon Sales Engineer.

The Thumbtack Probes are customizable according to the options detailed in the table below. It may also be possible to produce arrays beyond the specifications listed. It is recommended that you discuss your needs with a Plexon Sales Engineer to determine if your unique request can be accommodated and/or the most ideal configuration for your research needs.

Feature Specifications and Options Remarks
Applications In vivo; chronic or acute
Electrode channels 8, 16, or 24
Probe length 3mm
Shaft diameter 210μm or 500μm
Electrode Sites 15μm or 40μm diameter, platinum/iridium
Tip profile Rounded, dome-shaped
Inter-electrode spacing 50 to 500μm Spacing is customizable within range provided, however 100μm is typical.
Distance from tip to electrode 450μm
Silicone tube length between connector and probe 10cm Other lengths available upon request.
Silicone disk dimensions 8mm diameter disk,
0.15mm thick
Other dimensions available upon request.
Connector interface CON/32m-V 24 channel, 36-pin Omnetics connector with 0.025″ pitch. Also available in Nickel-free for MRI-compatibility

*Thumbtack Probes are manufactured by Neuronelektród.