Iridium Electrodes, Standard Tip

(MicroProbes)
Description

Iridium and Platinum-Iridium alloy are considered by many to be the "gold standard" for chronic recording and microstimulation due to its excellent electrochemical and mechanical characteristics.

Advantages Disadvantages
  • Pure Iridium can be electrochemically “activated” to create a layer of iridium oxide on the metal surface, imbuing it with exceptional electrochemical performance. These activated iridium oxide film (AIROF) electrodes offer some of the best stimulation performance known due to the fast faradaic charge transfer mechanisms available within the film.
  • Pure Iridium is appropriate for very aggressive stimulation protocols or very small electrode sizes.
  • Exceptional hardness and rigidity.
  • High cost due to the specialty nature of the material.
  • Only available in 100 micron diameter size.

These monopolar microelectrodes of MicroProbes are also available in Tungsten, Elgiloy (an alloy similar to stainless steel), and Platinum-Iridium alloy. The electrodes are insulated with a thin film of vapor-deposited Parylene-C. As an option we provide them surrounded by Polymide tubing. Each electrode is etched to a fine taper and tipped using a proprietary process to a specific impedance value. Four different tip profiles are also available to further fine-tune your electrode selection to your particular application.

We offer a variety of different tip alternatives for those that prefer a specialized electrode profile for their research.

The tip selection can provide subtle yet important changes to the performance of the electrode, as described below. It is recommended that first time users consider experimenting with different tip profiles to determine which works best for their recording or stimulation protocols.

For some applications concentric or bipolar electrodes (stereotrodes) are useful.

 

Monopolar Electrodes, Pure Iridium, Standard Tip
(100 µm × 2")

Item

Length

Shaft Diameter

Tip Diameter

Impedance

Applications

Pkg of 10

IR20030.01A4

51 mm

0.106 mm

2-3 µm

0.01 MΩ

Multiunit & ERP recording & stim.

IR20030.05A4

51 mm

0.106 mm

0.05 MΩ

IR20030.1A4

51 mm

0.106 mm

0.1 MΩ

IR20030.5A4

51 mm

0.106 mm

0.5 MΩ

Single & multiunit rec. & stim.

IR20031.0A4

51 mm

0.106 mm

1-2 µm

1.0 MΩ

IR20031.5A4

51 mm

0.106 mm

1.5 MΩ

IR20032.0A4

51 mm

0.106 mm

2.0 MΩ

Greater selectivity & micro. stim.

IR20032.5A4

51 mm

0.106 mm

2.5 MΩ

Greater Selectivity - Small Cells

IR20033.0A4

51 mm

0.106 mm

3.0 MΩ

IR20035.0A4

51 mm

0.106 mm

5.0 MΩ

 

Common Tip Profiles:

Scheme of Standard Tip Profile
A - STANDARD TIP PROFILE
The standard tip profile features a sharp yet robust point that offers versatile performance and an effective balance between penetration and durability.
Scheme of Blunted Tip Profile
B - BLUNTED TIP PROFILE
The blunted electrodes are engineered to have a more rounded, bullet-shaped tip. For many applications the blunted tip can offer superior stimulation performance.
Scheme of Heat Treated Tapered Tip Profile
H - HEAT TREATED TAPERED TIP PROFILE
The heat-treated electrodes are intended for those investigators who must penetrate their probes through tough membranes, such as the dura mater of larger mammals.
Scheme of Extra Fine Tip Profile
F - EXTRA FINE TIP PROFILE
The extra-fine tip profile features a significantly sharper taper as well as a thinner insulation layer. Available in Tungsten only!

 

Also see:

Selecting the Optimum Electrode Configuration