Tunable Electrode Gel Beads for Electrophysiology
Health Medicine and Biotechnology
Tunable Electrode Gel Beads for Electrophysiology (MSC-TOPS-151)
Provides mess-free electrode gel solution for electrophysiology instruments
Overview
Innovators at NASA Johnson Space Center have developed an electrode gel solution whose form factor is not a traditional salve, but a silica-based hydrogel bead. The bead’s absorbent properties allow the bead to con-tain liquid solutions whose chemical electrolyte composition can be calibrated to the type of monitoring, or stimulating, of electrical signals within the body via its conductive properties.
Electrode gels work by reducing the resistance at the electrode-skin tissue interface, thereby improving signal quality. However, conventional electrode gels are dispensed via a squeeze tube directly onto an elec-trode by trained operators and can be burdensome and messy, leaving gel residue on patients. This is especially true in time-consuming appli-cations like EEGs where a single system can possess hundreds of electrodes. Furthermore, current electrode gels are one-time use, have limited shelf lives, and are not calibrated for multiple electrophysiology instruments.
The Electrode Gel Bead addresses these shortcomings of COTS elec-trode gels due in part to the very nature of its soft “dry” outer casing containing a calibrated conductive solution that can be reused up to 10 times by reflourishing. The Electrode Gel Bead has a technology readi-ness level (TRL) 4 (component and/or breadboard validation in laboratory environment), and is now available for patent licensing. Please note that NASA does not manufacture products itself for commercial sale.
The Technology
The Electrode Gel Bead technology was developed to address specific challenges for crewed spaceflight in the event of medical intervention where bioelectric monitoring or stimulation is desired.
As mentioned, conventional electrode gels are traditionally dispensed from a tube onto an electrode, then washed off and discarded. For spaceflight applications, consumables of this nature are avoided due to mass and volume constraints, and to refrain from introducing solid contaminants into a closed spacecraft environment.
Electrode Gel Beads are versatile within electrophysiology applica-tions and can also be used for bioelectrical stimulation. Systems designed to electrically stimulate the body such as transcutaneous electrical nerve stimulation (TENS), and various brain stimulation devices, could benefit from this technology as electrode gels can evaporate causing electrodes to overheat and irritate or burn the patient’s skin. Electrode Gel Beads could solve this issue when correctly calibrated for the application.
To create a bead’s interior solution, a water/electrolyte mixture is calibrated with a specific molar concentration to create the necessary resistance for a specific electrophysiology application (different methods require a gel with different resistances such as ECG, EEG, etc.). Next, the solution is absorbed into an absorbent silica-based hydrogel bead. Hydrogel beads contain crosslinked polymer networks that can absorb and retain significant amounts of water without dissolving. They can absorb and retain significant amounts of the solution but maintain their structural integrity. After absorbing the solution, the hydrogel bead containing the solution can be affixed to an electrode and function as an electrode gel.
Terrestrial applications for the Electrode Gel Bead may exist in inpatient, outpatient, and in-home healthcare usage where mess-free, reusable, ease-of-use, and electrical signal quality attributes are desired. This technology could also have applications in hydrogel sensory materials, such as wearable sensors.
Benefits
- Soft bead form factor
- Self-contained bead solution can be calibrated for specific electrophysiology instruments
- Mess-free application
- Suitable for monitoring and stimulation
- Reusable
- Reliable and repeatable signal quality
- Time-saving application
- Suitable for inpatient, outpatient, and home healthcare
- Increased comfort for patients
Applications
- Inpatient and outpatient medical services
- Home healthcare
- Space-based micro-gravity medical intervention
- Hydrogel sensory materials
Technology Details
Health Medicine and Biotechnology
MSC-TOPS-151
MSC-27805-1
Patent Pending
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