PDMS/CNT electrodes with bioamplifier for practical in-the-ear and conventional biosignal recordings.

Potential usage of dry electrodes in emerging applications such as wearable devices, flexible tattoo circuits, and stretchable displays requires that, to become practical solutions, issues such as easy fabrication, strong durability, and low-cost materials must be addressed. The objective of this study was to propose soft and dry electrodes developed from polydimethylsiloxane (PDMS) and carbon nanotube (CNT) composites. Connected with both conventional and in-house NTAmp biosignal instruments for comparative studies, performances of the proposed dry electrodes were evaluated through electromyogram (EMG), electrocardiogram (ECG), and electroencephalogram (EEG) measurements. Results demonstrated that the capability of the PDMS/CNT electrodes to receive biosignals was on par with that of commercial electrodes (adhesive and gold-cup electrodes). Depending on the type of stimuli, a signal-to-noise ratio (SNR) of 5-10 dB range was achieved. The results of the study show that the performance of the proposed dry electrode is comparable to that of commercial electrodes, offering possibilities for diverse applications. These applications may include the physical examination of vital medical signs, the control of intelligent devices and robots, and the transmission of signals through flexible materials.