We fabricate silicon-based probes comprising typically 8 to 64 electrodes per shaft. The electrodes can be positioned in a tetrode configuration, a laminar distribution or randomly along the probe shafts. In general, we use Platinum (Pt), Iridium Oxide (IrOx) or Gold (Au) as electrode material. Aside from standard silicon probe layouts listed in our catalog, we also offer custom-design probes. Please contact us in case you would like to receive more information on our custom-design probe service.
All probe shafts can be equipped with a pointy tip feature instead of the standard chisel-shape tip. The pointy tip significantly reduces any dimpling effect during probe insertion. There is no need to cut or puncture the dura which decreases the risk on bleeding and infection. Another key feature of our silicon probe technology is the flexibility of the silicon shaft. Our silicon probes have had a special treatment which makes them bendable. The flexible shaft is suitable to load into existing hyperdrives such as the Kloosterman drive (Michon et al.) or the Flex drive of Open-Ephys.
Once removing the probe always prevent that any organic residue can dry-out on the probe shaft, flush it with deionized water, alcohol and rinse again with deionized water. Next, hold the silicon shaft in 1% tergazyme solution for 30-60min and flush it with deionized water. The silicon shaft should be shiny and is ready to use again.
We do have probe layouts available for all types of experimental setups, however those can be differentiated in three main categories: active, chronic and semi-chronic probe layouts. The three different probe layouts are summarized below.
The silicon probe is assembled onto a rigid printed circuit board (PCB), which can be attached onto the stereotactic frame and is often used in acute setups. Depending on the amount of channels, different connectors can be used such as DIL, MOLC, Micro Omnetics, etc... The different PCB layouts can be found when selecting the acute check-box in our digital probe catalog.
Acute probe layouts can be reused for several times. Simply respect the suggested cleaning procedure which is listed above.
The silicon probe is assembled onto a 3-cm-long ultra-flexible polyimide cable designed to interface with a ZIF-plug or Omnetics connector. The chronic layout is perfectly suitable for chronic experiments and setups where it is recommended to mechanically decouple the connector from the silicon probe. Chronic probe are implanted using the inserter tool and show great results in bigger size animal-models. The chronic probe is implanted using a dedicated reusable insertion tool, shown in the accessories subpage. There is a variety of connector types that we can assemble at the other side of the flex cable so we can make sure your existing headstage will be compatible with the electrode array.
The silicon probe is assembled as close to the connector as possible. This is the most compact probe layout and perfectly suitable for small-animal models in acute and chronic setups. This probe layout typically makes use of nano Omnetics connectors and the different layouts can be found when selecting the semi-chronic check-box in our digital probe catalog.
These thin-film, polyimide-based electrode arrays were developed in collaboration with the MICAS division (KULeuven, Belgium) and are ideal for long-term chronic stimulation and recording. The arrays are just 7 µm thick and micro-machined in a shape that allows flexibility and stretchability and are therefore suitable for placement over curved surfaces. There are openings in the array allow for easy combination with optogenetics and penetrating electrode arrays. The electrodes have been tested in vivo for up to one year. Custom designs are also possible on request.
Ceyssens, F., Puers, B. (2015). Insulation lifetime improvement of polyimide thin film neural implants. Journal of Neural Engineering, 12 (5), art.nr. 054001.