Surface electromyography using dry polymeric electrodes

Area of Science:

• Biomedical Engineering
• Materials Science
• Neuroscience

Background:

• Conventional wet Ag/AgCl electrodes are standard for biopotential measurements but have limitations like extensive skin prep and short-term use.
• Dry electrodes offer advantages for surface electromyography (sEMG) due to convenience, durability, and suitability for continuous monitoring.

Purpose of the Study:

• To explore conductive elastomers (CEs) based on PEDOT:PSS in polyurethane as dry, skin-contacting electrodes for EMG recording.
• To compare the performance of these novel dry CE electrodes against commercial wet Ag/AgCl electrodes.

Main Methods:

• Developed dry conductive elastomer electrodes incorporating PEDOT:PSS within a polyurethane matrix.
• Tested electrodes on five subjects performing four distinct movements (open hand, fist, wrist extension, wrist flexion).
• Utilized a backpropagation artificial neural network to classify movements based on recorded EMG signals.

Main Results:

• Dry conductive elastomer electrodes achieved a movement classification accuracy of 99.5%.
• Commercial wet Ag/AgCl electrodes achieved a classification accuracy of 98.7%.
• PEDOT-based dry CEs demonstrated comparable performance to Ag/AgCl electrodes.

Conclusions:

• Dry PEDOT-based conductive elastomer electrodes are effective for on-skin EMG recording.
• These dry electrodes overcome limitations of wet electrodes, enabling minimal skin preparation and gel-free, long-term wearable applications.