Cohesive dry ECG sensor using silver nanowires and PDMS tuned for adhesion

Abstract

A technique is exploited to develop a dry ECG sensor using polydimethylsiloxane (PDMS) with enhanced adhesion to skin. The sensor consists of silver nanowires (AgNWs) embedded in PDMS. The adhesive solution presented is a novel technique which combines using high‐ratio 25:1 PDMS selectively deposited in a thin layer on the surface of a sensor body that is made from 15:1 PDMS. With this adhesive mechanism, we demonstrate a cohesive ECG sensor which can adhere to a subject without the use of additional sticky adhesives and that is compatible with current ECG technology. PDMS is residue free and highly biocompatible meaning this is a solution suitable for long‐term wear. We demonstrate that our sensor can be filtered to similar quality of a traditional ECG sensor, and further show that our sensors stay in place for more than 24 hr and it can adhere to skin with an average maximum force of about 1.09 N.

Fabrication of Silver Nanowire/Polydimethylsiloxane Dry Electrodes by a Vacuum Filtration Method for Electrophysiological Signal Monitoring

“…Additionally, due to their invasive nature and the risk of microneedle breakage during the insertion process, they are not suitable for long-term signal monitoring. − (d) Silver nanowires (AgNWs) and polydimethylsiloxane (PDMS)-based flexible dry electrodes have been previously fabricated by drop-casting methods. However, adhesion of AgNWs with PDMS and cytotoxicity of AgNWs and PDMS-based dry electrodes have not been evaluated in studies. − …”

Stretchable and Directly Patternable Double-Layer Structure Electrodes with Complete Coverage

“…Stretchable electrodes have been spotlighted because they are used in numerous wearable electronic devices, such as Internet-of-things (IoT) sensors, − medical and health care devices, − textiles for electronic skins, − and human–robotic interactions. , Various functional materials have been investigated to produce stretchable electrodes without significantly compromising their mechanical and electrical properties during stretching. Extended studies have focused on the development of efficient, robust, stretchable, and conductive electrodes. − Recent studies concerning the development of stretchable electrodes are classified according to the material type.…”

Metal nanoparticles as an electromagnetic microwave heat-cure agent for polydimethylsiloxane elastomers

“…Polydimethylsiloxane (PDMS) appears to be one of the most common choices as a base polymer for flexible electronics, in particular due the ease of production and bio-compatibility. Silver nanoparticles (Ag NPs) and nanowires (Ag NWs) are often combined with PDMS [1] as a filler for wearable [2 -4], sensorics [5,6], biological [7] and medical [8] applications. It is generally known that PDMS-based materials offer high flexibility and stretchability, and their surface is expected to be hydrophobic, but the exact functional properties can strongly depend on the material content and processing.…”