{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T03:48:44Z","timestamp":1760240924792,"version":"build-2065373602"},"reference-count":43,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2019,10,22]],"date-time":"2019-10-22T00:00:00Z","timestamp":1571702400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Information"],"abstract":"<jats:p>Flexible paper-based physiological sensor electrodes were developed using chemically-modified graphene (CG) and carboxylic-functionalized multiwalled carbon nanotube composites (f@MWCNTs). A solvothermal process with additional treatment was conducted to synthesize CG and f@MWCNTs to make CG-f@MWCNT composites. The composite was sonicated in an appropriate solvent to make a uniform suspension, and then it was drop cast on a nylon membrane in a vacuum filter. A number of batches (0%~35% f@MWCNTs) were prepared to investigate the performance of the physical characteristics. The 25% f@MWCNT-loaded composite showed the best adhesion on the paper substrate. The surface topography and chemical bonding of the proposed CG-f@MWCNT electrodes were characterized by scanning electron microscopy (SEM) and Raman spectroscopy, respectively. The average sheet resistance of the 25% CG-f@MWCNT electrode was determined to be 75 \u03a9\/\u25a1, and it showed a skin contact impedance of 45.12 k\u03a9 at 100 Hz. Electrocardiogram (ECG) signals were recorded from the chest and fingertips of healthy adults using the proposed electrodes. The CG-f@MWCNT electrodes demonstrated comfortability and a high sensitivity for electrocardiogram signal detection.<\/jats:p>","DOI":"10.3390\/info10100325","type":"journal-article","created":{"date-parts":[[2019,10,23]],"date-time":"2019-10-23T11:46:59Z","timestamp":1571831219000},"page":"325","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":33,"title":["Paper-Based Flexible Electrode Using Chemically-Modified Graphene and Functionalized Multiwalled Carbon Nanotube Composites for Electrophysiological Signal Sensing"],"prefix":"10.3390","volume":"10","author":[{"given":"Md Faruk","family":"Hossain","sequence":"first","affiliation":[{"name":"Department of Medicine, University of Connecticut School of Medicine, Farmington, CT 06030, USA"},{"name":"Center for Bioelectrics, Old Dominion University Research Foundation, Norfolk, VA 23508, USA"}]},{"given":"Jae Sang","family":"Heo","sequence":"additional","affiliation":[{"name":"Department of Medicine, University of Connecticut School of Medicine, Farmington, CT 06030, USA"}]},{"given":"John","family":"Nelson","sequence":"additional","affiliation":[{"name":"Department of Medicine, University of Connecticut School of Medicine, Farmington, CT 06030, USA"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6539-1776","authenticated-orcid":false,"given":"Insoo","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Medicine, University of Connecticut School of Medicine, Farmington, CT 06030, USA"},{"name":"Department of Biomedical Engineering, University of Connecticut, Storrs, CT 06269, USA"}]}],"member":"1968","published-online":{"date-parts":[[2019,10,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1375","DOI":"10.1038\/s41598-017-18209-w","article-title":"Simple and cost-effective method of highly conductive and elastic carbon nanotube polydimethylsiloxane composite for wearable electronics","volume":"8","author":"Kim","year":"2018","journal-title":"Sci. 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