Flexible dry surface-electrodes for ECG long-term monitoring

Abstract

In this paper a new generation of dry electrodes for ECG-recording purposes is presented. These electrodes are flexible, biocompatible, biostable and perform a dry signal acquisition without the use of any electrolyte gel or adhesive. Thereby no skin preparation is needed. The material properties allow integration into textiles to form intelligent clothes for long-term monitoring duties. The electrodes can be washed together with the carrier textiles and provide a very good wearing comfort resulting in wide acceptance by the patients. The Department Medical Engineering and Neuroprosthetics of the Fraunhofer Institute for Biomedical Engineering developed these electrodes mainly to process the Electrocardiogram, however, in first tests they proved their capability even for other biosignal requirements like surface-EMG. In either case the signal quality of the dry electrodes is comparable to commercial Ag/AgCl gel-electrodes.

Smartware electrodes for ECG measurements : Design, evaluation and signal processing

“…To overcome this, it is often reported that the electrodes should be applied some time prior to the tests, for example in [5,115]. This is to take advantage of the sweat generation underneath the electrode surface since sweat includes Author Material Construction method Beckmann et al [9] SS/silver/copper knit/weave/coating Marozas et al [65] silver plated nylon thread embroidery Hoffmann et al [43] carbon nano tubes foam Negru et al [79] carbon black coated weave Noury et al…”

“…There are how-ever, several other modalities mentioned in the literature. A foam like electrode was created by Hoffmann et al [43]. The foam electrode was doped with carbon nano tubes and an electrolyte, which showed excellent properties of square resistance.…”

“…Jiang et al [47] has tested the biostability of polypyrrole coated polyester with good results. Tests have also been carried out to test the biostability of the foam electrodes used in Hoffmann [43].…”

Fully:Textile Polymer:Based ECG Electrodes: Overcoming the Limits of Metal:Based Textiles

“…Originally developed to replace off-the-shelf disposable gelled Ag/AgCl electrodes, the gold standard for clinical and short-term recording but limited by short operating time and poor comfort, traditional textile electrodes used without any conductive hydrogel failed to provide an effective way to access high-quality ECG signal [8]. High skin-electrode contact impedance, the consequently higher mains interference, the typically large baseline wandering artefact, the presence of the metal wires directly in contact with the skin, are the most remarkable problems associated to their use [9].…”

Identification of sleep apnea events using discrete wavelet transform of respiration, ECG and accelerometer signals

“…The ECG signal was recorded using two moistened fabric sensors located at either side of the ribcage (Figure 1 (b)). The use of these fabric electrodes eliminates the requirement for adhesive electrodes which can be cumbersome to apply and have been shown to occasionally cause skin irritation [10], while also allowing for unlimited use. The ECG signal was recorded at a sampling rate of 250 Hz.…”