Biopotential Skin Electrodes

Gereonics Electrodes

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Electrodes Dimensions:
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Quality Reusable  Electrodes

• Stable, low noise measurements
• Low artifact susceptibility
• Integral and snap lead wires
• Easily attached
• Tough
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Gereonics Biopotential Skin Electrodes transmit stable and clean signals for precise physiological measurements.





They are especially suitable for sleep disorders testing, exercise testing or for pediatric and adult monitoring and recording.

Applications include ECG, EOG, ENG, EMG, EEG, GSR, and evoked potentials.


Rugged Design in Standard and Miniature Sizes

Gereonics electrode bodies are manufactured using FDA quality high impact plastic.
The flexible, durable and finely stranded lead wires are sized to be compatible with the "STANDARD" and "Miniature" (20 and 11mm O.D.) electrodes. They are available in five lead wire colors. The standard size electrodes are available in snap and integral lead wire designs to suit the application. The electrodes are terminated in standard 1.5mm (0.60in.) female safety connectors.

Low Drift and Motion Artifact Design

The specially compounded sensing element of silver and silver chloride is the key to precision low drift design. As a result, offset voltage and polarization - two key performance parameters, are unsurpassed. The electrodes never need to be rechloridized.

Easily Applied and Cleaned

Gereonics electrodes are attached to the skin using adhesive washers.
Relatively large electrode body surface areas provide excellent skin adhesion especially where motion may affect signal quality. The open cavity design allows the electrolyte gel or cream to be easily applied and quickly cleaned using distilled or deionized water.


Gereonics electrodes can be used many dozens of times and maintain their quality performance characteristics. They are often used in lieu of disposable electrodes where cost and quality considerations are of paramount importance.

Instructions for Use...

When using new electrodes, or electrodes left dry for several weeks, provide initial stabilization by soaking the electrodes in normal saline (0.83% w/w) or a prepared 1.0% (10g/l) sodium chloride solution for at least three hours.
Soaking in deionized or distilled water is also acceptable.

The skin should be clean where electrodes will be attached. The cavity and surface of the electrode should also be clean and dry to attach the adhesive washer and to fill the cavity with electrolyte gel or cream. Remove the adhesive washer from its backing strip using the blue tab, and apply the adhesive washer carefully to center the hole over the electrode cavity. Press the washer down to seal the surface of the electrode.


Squeeze sufficient electrolyte gel or cream to just fill the cavity. Check carefully to see that no air bubbles were introduced into the cavity. Remove the round backing paper from the second side of the adhesive washer and place the electrode on the prepared skin surface. Press the electrode down firmly to attach and seal the electrode to the skin. The exposed adhesive area of the washer may be rubbed with gel or cream to eliminate its adhesive qualities.

If skin is heavily cornified, abrade area where electrode is to be attached. Rub gel or cream into skin at this spot. Allow several minutes to soak in and then wipe skin and dry before attaching electrode.





Clean skin with 70% isopropyl alcohol by rubbing briskly.
Remove paper from one side of adhesive washer and press
washer on electrode face.
Squeeze electrolyte gel or cream into electrode cavity.
Remove second cover from adhesive washer and press electrode
onto clean skin. Change electrode location daily.

Cleaning Electrodes...

Immediately after removing the electrode, take off the adhesive washer and
wash out the gel or cream using distilled or deionized water. A plastic wash
bottle with squirt tip is very suitable. Never use tap water. A cotton swab can
be used to remove the main bulk of the gel or cream. Soak the electrode in a
mild saline solution until the next application. Your lab or hospital may have
normal saline solution available in prepared bottles. Do not let the old gel or
cream dry or harden in the cavity.

Other Cleaning Tips...

If electrodes are used only occasionally, a brown coating may form over the
sensing element. This can be removed by wiping with a mild ammonium hydroxide
solution or by lightly abrading with a very thin strip of 200 mesh emery

Electrodes will turn black if continuously exposed to bright light. The
finely divided silver in the electrode pellet oxidizes to silver oxide (black)
much like a photographic negative. The electrode will perform normally even when
the appearance is almost jet black. Cleaning by abrasion to remove the oxide
layer is appropriate, however. Store electrodes in use in a dark drawer or a
closed opaque box.

Electrodes can be permanently damaged (poisoned) when only small amounts of
bromide, sulfide and other metal ions are present. Do not expose the electrodes
to tap water, EEG pastes containing abrasive clays, miscellaneous soap solutions
or abrasive cleaners.


This procedure is one of the methods endorsed by the Board of Trustees of the
American Society of Electroneurodiagnostic Technologists (Am. J. EEG Technol.
35: 3-36, 1995). The sodium hypochlorite procedure is the simplest, safest and
most economical method for “high level disinfection”. Gereonics electrodes are
unaffected by dozens of disinfections using this method.

  1. Purchase 5.25% sodium hypochloride (NaOCl) as household Clorox or Purex
    bleach. There are a plethoraof “bleach” solutions containing detergents and
    other additives. Obtain only pure bleach containing 5.25% NaOCl and water.
  2. This bleach solution can be used as a high level disinfectant for Gereonics
    electrodes using a 1:50 (1000 ppm) dilution of 5.25% sodium hypochlorite for a
    period of twenty minutes when mixed fresh and used within 24 hours. A 1:50
    dilution means to add one part bleach solution to 49 parts of distilled or
    deionized water; for example, 2cc of bleach to 98cc of water.
  3. When electrodes have soaked for twenty minutes, remove from the diluted
    (1000 ppm) bleach solution, rinse the electrodes off using a deionized or
    distilled water spray bottle and immerse them in a normal saline solution. The
    electrodes will return to very acceptable Noise and DC Offset Voltage levels in
    90 minutes, i.e. suitable for use. Do not soak electrodes in the diluted bleach
    solution for extended periods of time as the oxygen will cause a blackening of
    the electrode. This does not affect electrode performance. Please consult with
    Gereonics if you wish to use other disinfection procedures.


Gereonics silver/silver chloride electrodes may be sterilized using the low
temperature peroxide sterilization method. This utilizes the STERRAD 100
Sterilizer from Advanced
Sterization Products, a Johnson & Johnson Company.