Enhancement of electrode design for non-invasive stimulus application

Existing electrodes can be classified into two categories which are invasive and non-invasive electrodes. The non-invasive electrodes can be further classified into wet or dry electrodes. Most of the off-the-shelf electrodes are made from rigid substrates which have the high level of motion artifacts. To overcome this motion artifact, flexible electrodes have been slowly introduced in the market. Flexible electrodes can be made from various types of material such as the substrate. This paper presents a work on designing a new flexible dry electrodes using poly(3,4-ethylenedioxythiophene) polystyrene sulfonate and silver by means of dispenser printing technology. Polyester cotton fabric was selected as the substrate in this electrode designed. Results from the experiment show that the conductivity of the proposed flexible electrode is comparable with the conventional pre-gelled electrode when applied to an electrical stimulator device. Eight out of ten subjects under test described no difference in comfort between the proposed electrodes and pre-gelled electrodes. © 2017 IEEE

Development of a Flexible Non-Metal Electrode for Cell Stimulation and Recording

This study presents a method of producing flexible electrodes for potentially simultaneously stimulating and measuring cellular signals in retinal cells. Currently, most multi-electrode applications rely primarily on etching, but the metals involved have a certain degree of brittleness, leaving them prone to cracking under prolonged pressure. This study proposes using silver chloride ink as a conductive metal, and polydimethysiloxane (PDMS) as the substrate to provide electrodes with an increased degree of flexibility to allow them to bend. This structure is divided into the electrode layer made of PDMS and silver chloride ink, and a PDMS film coating layer. PDMS can be mixed in different proportions to modify the degree of rigidity. The proposed method involved three steps. The first segment entailed the manufacturing of the electrode, using silver chloride ink as the conductive material, and using computer software to define the electrode size and micro-engraving mechanisms to produce the electrode pattern. The resulting uniform PDMS pattern was then baked onto the model, and the flow channel was filled with the conductive material before air drying to produce the required electrode. In the second stage, we tested the electrode, using an impedance analyzer to measure electrode cyclic voltammetry and impedance. In the third phase, mechanical and biocompatibility tests were conducted to determine electrode properties. This study aims to produce a flexible, non-metallic sensing electrode which fits snugly for use in a range of measurement applications