Monopolar Tungsten Microelectrodes, Blunted Tip (MicroProbes)

Description

Tungsten is a versatile and widely-used microelectrode material that offers a good balance between performance and cost.

Advantages

Disadvantages

Extremely strong and stiff metal provides probes with exceptional rigidity.
Great for acute and chronic recording due to biocompatibility and lower cost.
High corrosion resistance offers consistent long-term performance.

Does not provide the same degree of electrochemical performance or stability as platinum-iridium alloy, making it a poor alternative for microstimulation.
Lower charge transfer capacity of tungsten will result in larger, potentially unsafe interfacial potentials when applying the same stimulation current as to a platinum-iridium electrode.
Certain pH or stimulation conditions can lead to tungsten corrosion.

These monopolar microelectrodes of MicroProbes are also available in Platinum/Iridium, Elgiloy (an alloy similar to stainless steel), and Pure Iridium metal. 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 available, as described below.

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. 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, Tungsten, Blunted Tip
(75 µm × 3")

Item	Length	Shaft Diameter	Tip Diameter	Impedance	Applications	Pkg of 10
WE30030.01B3	76 mm	0.081 mm	3-5 µm	0.01 MΩ	MultiUnit & ERP recording & Stim
WE30030.05B3	76 mm	0.081 mm		0.05 MΩ
WE30030.1B3	76 mm	0.081 mm		0.1 MΩ
WE30030.5B3	76 mm	0.081 mm		0.5 MΩ	Single & multiunit rec. & stim.
WE30031.0B3	76 mm	0.081 mm	3-4 µm	1.0 MΩ
WE30031.5B3	76 mm	0.081 mm		1.5 MΩ
WE30032.0B3	76 mm	0.081 mm		2.0 MΩ
WE30032.5B3	76 mm	0.081 mm		2.5 MΩ	Greater Selectivity - Small Cells
WE30033.0B3	76 mm	0.081 mm		3.0 MΩ	Greater Selectivity - Small Cells

Monopolar Electrodes, Tungsten, Blunted Tip
(125 µm × 3")

Item	Length	Shaft Diameter	Tip Diameter	Impedance	Applications	Pkg of 10
WE30030.01B5	76 mm	0.131 mm	3-5 µm	0.01 MΩ	MultiUnit & ERP recording & Stim
WE30030.05B5	76 mm	0.131 mm		0.05 MΩ
WE30030.1B5	76 mm	0.131 mm		0.1 MΩ
WE30030.5B5	76 mm	0.131 mm		0.5 MΩ	Single & multiunit rec. & stim.
WE30031.0B5	76 mm	0.131 mm	3-4 µm	1.0 MΩ
WE30031.5B5	76 mm	0.131 mm		1.5 MΩ
WE30032.0B5	76 mm	0.131 mm		2.0 MΩ
WE30032.5B5	76 mm	0.131 mm		2.5 MΩ	Greater Selectivity - Small Cells
WE30033.0B5	76 mm	0.131 mm		3.0 MΩ
WE30035.0B5	76 mm	0.131 mm		5.0 MΩ

Monopolar Electrodes, Tungsten, Blunted Tip
(250 µm × 3")

Item	Length	Shaft Diameter	Tip Diameter	Impedance	Applications	Pkg of 10
WE30030.01A10	76 mm	0.256 mm	3-5 µm	0.01 MΩ	MultiUnit & ERP recording & Stim
WE30030.05A10	76 mm	0.256 mm		0.05 MΩ
WE30030.1A10	76 mm	0.256 mm		0.1 MΩ
WE30030.5A10	76 mm	0.256 mm		0.5 MΩ	Single & multiunit rec. & stim.
WE30031.0A10	76 mm	0.256 mm	3-4 µm	1.0 MΩ
WE30031.5A10	76 mm	0.256 mm		1.5 MΩ
WE30032.0A10	76 mm	0.256 mm		2.0 MΩ
WE30032.5A10	76 mm	0.256 mm		2.5 MΩ	Greater Selectivity - Small Cells
WE30033.0A10	76 mm	0.256 mm		3.0 MΩ	Greater Selectivity - Small Cells

Monopolar Electrodes, Tungsten, Blunted Tip
(125 µm × 5")

Item	Length	Shaft Diameter	Tip Diameter	Impedance	Applications	Pkg of 10
WE50030.01B5	127 mm	0.131 mm	3-5 µm	0.01 MΩ	MultiUnit & ERP recording & Stim
WE50030.05B5	127 mm	0.131 mm		0.05 MΩ
WE50030.1B5	127 mm	0.131 mm		0.1 MΩ
WE50030.5B5	127 mm	0.131 mm		0.5 MΩ	Single & multiunit rec. & stim.
WE50031.0B5	127 mm	0.131 mm	3-4 µm	1.0 MΩ
WE50031.5B5	127 mm	0.131 mm		1.5 MΩ
WE50032.0B5	127 mm	0.131 mm		2.0 MΩ
WE50032.5B5	127 mm	0.131 mm		2.5 MΩ	Greater Selectivity - Small Cells
WE50033.0B5	127 mm	0.131 mm		3.0 MΩ	Greater Selectivity - Small Cells

Monopolar Electrodes, Tungsten, Blunted Tip
(250 µm × 5")

Item	Length	Shaft Diameter	Tip Diameter	Impedance	Applications	Pkg of 10
WE50030.01A10	127 mm	0.256 mm	3-5 µm	0.01 MΩ	MultiUnit & ERP recording & Stim
WE50030.05A10	127 mm	0.256 mm		0.05 MΩ
WE50030.1A10	127 mm	0.256 mm		0.1 MΩ
WE50030.5A10	127 mm	0.256 mm		0.5 MΩ	Single & multiunit rec. & stim.
WE50031.0A10	127 mm	0.256 mm	3-4 µm	1.0 MΩ
WE50031.5A10	127 mm	0.256 mm		1.5 MΩ
WE50032.0A10	127 mm	0.256 mm		2.0 MΩ
WE50032.5A10	127 mm	0.256 mm		2.5 MΩ	Greater Selectivity - Small Cells
WE50033.0A10	127 mm	0.256 mm		3.0 MΩ	Greater Selectivity - Small Cells

Common Tip Profiles:

Standard — **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.

Blunted — **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.

Tapered — **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.

Extra Fine — **F - EXTRA FINE TIP PROFILE**
The extra-fine tip profile features a significantly sharper taper as well as a thinner insulation layer.

Also see:

Selecting the Optimum Electrode Configuration

Tungsten Electrodes, Blunted Tip

Also see: