Highly conformable stretchable dry electrodes based on inexpensive flex substrate for long-term biopotential (EMG/ECG) monitoring

Shqau

J of Applied Polymer Sci

et al. 2020

A new material, classified as a soft mixed ionic–electronic conductor (MIEC), was fabricated through casting and curing of different ratios of single walled carbon nanotube (SWNTs), hyaluronic acid (HA), and acrylonitrile butadiene copolymer latex (NBR) and developed for noninvasive stimulation for electrotherapeutics. The morphology of the composite yielded high electrical conductivity and retention of elasticity. The interfacial charge transfer of the material showed that by increasing the HA loading the capacitive contribution decreased, while increasing SWNT loading decreased the interfacial resistance. The soft MIEC materials interfacial charge transfer was superior than current state‐of‐the art electrodes on the market. A layered configuration with high HA ratio at the skin interface and high SWNTs ratio at the stainless‐steel interface was created to induce the most optimal charge transfer. These soft MIEC electrodes will be extremely helpful in electrotherapeutic applications to eliminate the need for hydrogels, which can be unsuitable due the their lack long term durability and instability.

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Soft mixed ionic–electronic conductive electrodes for noninvasive stimulation

Shqau

J of Applied Polymer Sci

et al. 2020

Breathable, Flexible, Transparent, Hydrophobic, and Biotic Sustainable Electrodes for Heating and Biopotential Signal Measurement Applications

et al. 2022

Flexible electronics is an interdisciplinary research area that combines a variety of research fields, such as chemistry, physics, material science, electronic and electrical engineering, mechanical engineering, computing science, and application-related fields such as biomedical engineering. [1] The outcomes are compliant devices that can maintain mechanical integrity and electrical functionality while they are lightweight and conformable over uneven surfaces. [2,3] Maintaining the mechanical and electrical integrity of the device during the deformation is the main challenge that needs to be addressed. [2] In response to the challenges, the development of novel flexible materials and special mechanical designs are key remedies in designing the substrates and active components used in flexible electronics. There are commonly used flexible materials as substrate and conductive layers: either organic [4,5] (e.g., small molecules, polymers) or inorganic [6,7] (e.g., metal nanowires, graphene, carbon nanotube). Likewise, different strategies in the structural design of stretchable systems are commonly used, such as in-plane/out-of-plane wavy structures, origami and kirigami structures as well as the islandbridge approach where rigid functional units are miniaturized and linked together by deformable interconnections. [8][9][10] Among various kinds of applications, healthcare devices, including skin patches, smart clothing, and other devices that interface with the skin or other tissues are increasing their importance in remote patient monitoring and treatment. [11] Learning from nature provides a tremendous number of lessons for scientists to develop new materials and designs. [12] Therefore, bioinspired materials with special functionalities have gained a lot of attention in engineering research. Scientists are inspired by the unique microstructures of these functional biological materials that can offer new features for various applications. [13,14] Among the number of biostructure patterns, fractal-like structures are available in nature. Examples of fractal-like structures in nature are snowflakes and leaf skeletons. Fractal-like designs which offer high surface area, improved stability, and efficient transport of ions in the materials have been

All 3D‐Printed Soft High‐Density Surface Electromyography Electrode Arrays for Accurate Muscle Activation Mapping and Decomposition

Zhao,

Chen,

et al. 2023

Adv Funct Materials

High‐density surface electromyography (sEMG) electrode arrays enable the recording of tens to hundreds of channels of electromyographic signals, which have found wide applications in clinics and human‐machine interfaces. However, current manufacturing technologies of high‐density sEMG electrode arrays generally involve high‐cost equipments, complicated procedures, and insufficient programmability, severely hampering the rational design and practical applications of customized yet cost‐effective high‐density electrode arrays. Herein, the facile and efficient fabrication of novel 32‐channel soft high‐density sEMG electrode arrays by an all‐printed technique based on multimaterial direct ink writing 3D printing is presented. By employing rational four‐layer stacked structure designs with systematic ink printability evaluation, it can successfully realize seamless interfacial integration during the multimaterial printing, achieving reproducible, programmable, continuous fabrication of soft high‐density sEMG electrode arrays. The all 3D‐printed soft electrode arrays exhibit excellent stability, low impedance, and high signal‐to‐noise ratio superior to commercial products with an increase of 32.2%. Such intriguing properties enable this all 3D‐printed electrode arrays the unique capability of mapping muscle activation of the forearm, and the motor unit action potential trains can be precisely identified for varying hand gestures to effectively explore the innovative human‐machine interface toward diverse applications such as teleoperation and prosthetic control.