Fructus Xanthii-Inspired Low Dynamic Noise Dry Bioelectrodes for Surface Monitoring of ECG

Abstract

The microstructured surfaces of bioelectrical dry electrodes are important aspects of dry electrode design. However, traditional surfaces for microstructured bioelectrical dry electrodes are costly to produce and require complex fabrication methods. In this study, a novel stacked-template method is proposed for the first time, rapidly producing microstructured dry electrodes at a low cost and with a large surface area. Three types of microstructured Ag/AgCl thermoplastic polyurethane (TPU) electrodes with a Fructus xanthii-inspired barb structure (FXbs) are prepared using this method; then, the dynamic friction, hair interference resistance, electrochemical, and electrocardiogram (ECG) signal acquisition performance of the electrodes are tested, and the dynamic noise characteristics of the electrodes are comprehensively evaluated with simulated instruments. Compared to the plate structure, the dynamic friction coefficient of the FXbs electrode improved by about 38.8%, exhibiting strong hair interference resistance. In addition, the FXbs electrode exhibits low dynamic noise and comparable performance to the wet electrode, in terms of signal acquisition, when it is tested using simulated instruments. Therefore, the prepared FXbs electrode increases the friction coefficient between the electrode and the skin, which effectively resolves issues related to dynamic noise in bioelectrical signals, making it suitable for dynamic measurements.

Insight into the Contact Impedance between the Electrode and the Skin Surface for Electrophysical Recordings

“… 5 There are three different types of noninvasive surface electrodes commercially available. 6 , 7 They are named the wet electrode, semidry electrode, 8 and dry electrode, 9 and their configurations are illustrated in Figure 1 . The wet electrode consists of the Ag/AgCl piece and the gel.…”

“…The electrode is the most crucial component for the surface electrical signal acquisition system, especially for EEG (electroencephalography), EMG (electromyography), and ECG (electrocardiograph) . There are three different types of noninvasive surface electrodes commercially available. , They are named the wet electrode, semidry electrode, and dry electrode, and their configurations are illustrated in Figure . The wet electrode consists of the Ag/AgCl piece and the gel.…”

Development of High-Sensitivity Piezoresistive Sensors Based on Highly Breathable Spacer Fabric with TPU/PPy/PDA Coating

“…PU@CNT films Solution modification 0-3 kPa 0-16 kPa 51.53 - [6] AgNWs/PU sponge dip-coating and precompression treatment -26.07 [12] PPy/PDMS Oxidative polymerization 0-1 19.32 [15] m-MWNT/PU Solution modification 0-63 4.282 Table 1 shows the comparison of the main performances of piezoresistive sensors reported by recent literature. It proved the feasibility of fabricating highly sensitive piezoresistive sensors by coating PPy with highly breathable spacer fabrics.…”

“…In recent years, flexible wearable pressure sensors have attracted widespread research interest due to their great potential for human activity detection, human-computer interaction interfaces, medical health testing, and artificial electronic skin [ 1 , 2 ]. By attaching flexible strain pressure sensors to the joints, wrists, and heart of the human, real-time monitoring of human movement status [ 3 ], pulse/heart rate [ 4 ], and ECG and EEG signals [ 5 , 6 ] and heart valves [ 2 ] can be achieved, providing early warning of the onsets of diseases. So far, piezoresistive [ 7 , 8 ], capacitive [ 9 ], and self-powered [ 10 , 11 ] sensors have been reported.…”

Ordered Nanopillar Arrays of Low Dynamic Noise Dry Bioelectrodes for Electrocardiogram Surface Monitoring

“…In recent years, dry electrodes are expected to replace wet electrodes in the field of medical devices to better meet the needs of people for long-term health monitoring and disease prevention. − Among them, penetrating dry electrodes reduce contact impedance by penetrating the stratum corneum without damaging skin tissues, , which is effective in reducing contact impedance but also prone to skin infection and inflammation. Compared with penetrating dry electrodes, the surface microstructure of flexible micro- and nanostructured electrodes can naturally fit the skin surface, can better adapt to the skin structure, and does not penetrate human skin, thus providing more comfortable, more stable, and lower impedance performance . More importantly, flexible dry electrodes have excellent biocompatibility and can significantly reduce the risk of inflammation, making them suitable for health monitoring in long-term healthcare. , …”