{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,15]],"date-time":"2026-04-15T09:08:58Z","timestamp":1776244138635,"version":"3.50.1"},"reference-count":41,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2022,3,10]],"date-time":"2022-03-10T00:00:00Z","timestamp":1646870400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003725","name":"National Research Foundation of Korea","doi-asserted-by":"publisher","award":["2021R1I1A1A01060078"],"award-info":[{"award-number":["2021R1I1A1A01060078"]}],"id":[{"id":"10.13039\/501100003725","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003621","name":"Ministry of Science ICT and Future Planning","doi-asserted-by":"publisher","award":["2021-0-01151"],"award-info":[{"award-number":["2021-0-01151"]}],"id":[{"id":"10.13039\/501100003621","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100013173","name":"Gyeonggi-do Regional Research Center","doi-asserted-by":"publisher","award":["2017-B06"],"award-info":[{"award-number":["2017-B06"]}],"id":[{"id":"10.13039\/501100013173","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The use of biopolymers for realizing economical and eco-friendly triboelectric nanogenerators (TENGs) widens the application prospects of TENGs. Herein, an animal-sourced whey protein isolate (WPI) film, processed and prepared by a simple aqueous solution preparation and drop-casting technique, is applied to demonstrate its potential use in bio-TENGs. With the addition of formaldehyde in WPI, the films result in a free-standing and flexible film, whereas the pure WPI films are difficult to handle and lack flexibility. A TENG device based on the WPI and the laser-ablated textured polydimethylsiloxane (PDMS) for pressure-sensor application were developed. The output voltage of the TENG comprising WPI increased nearly two-fold compared to the TENG without WPI. A simple single-electrode TENG device configuration was adopted so that it could be easily integrated into a wearable electronic device. Moreover, WPI film exhibited tribo-negative-like material characteristics. This study provides new insights into the development of biocompatible and eco-friendly biopolymers for various electronic devices and sensors.<\/jats:p>","DOI":"10.3390\/s22062154","type":"journal-article","created":{"date-parts":[[2022,3,10]],"date-time":"2022-03-10T20:19:10Z","timestamp":1646943550000},"page":"2154","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":16,"title":["Whey Protein Isolate Film and Laser-Ablated Textured PDMS-Based Single-Electrode Triboelectric Nanogenerator for Pressure-Sensor Application"],"prefix":"10.3390","volume":"22","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6226-4162","authenticated-orcid":false,"given":"Minwoo","family":"Lee","sequence":"first","affiliation":[{"name":"Multifunctional Nano Bio Electronics Lab, Department of Advanced Materials and Science Engineering, Sungkyunkwan University, Suwon 16419, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jonghwan","family":"Shin","sequence":"additional","affiliation":[{"name":"Multifunctional Nano Bio Electronics Lab, Department of Advanced Materials and Science Engineering, Sungkyunkwan University, Suwon 16419, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1747-4539","authenticated-orcid":false,"given":"Sunkook","family":"Kim","sequence":"additional","affiliation":[{"name":"Multifunctional Nano Bio Electronics Lab, Department of Advanced Materials and Science Engineering, Sungkyunkwan University, Suwon 16419, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4586-1483","authenticated-orcid":false,"given":"Srinivas","family":"Gandla","sequence":"additional","affiliation":[{"name":"Multifunctional Nano Bio Electronics Lab, Department of Advanced Materials and Science Engineering, Sungkyunkwan University, Suwon 16419, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,3,10]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"e12065","DOI":"10.1002\/eom2.12065","article-title":"Recent trends of biocompatible triboelectric nanogenerators toward self-powered e-skin","volume":"2","author":"Ganesh","year":"2020","journal-title":"EcoMat"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"42","DOI":"10.1007\/s40820-020-0373-y","article-title":"Natural and Eco-Friendly Materials for Triboelectric Energy Harvesting","volume":"12","author":"Slabov","year":"2020","journal-title":"Nano-Micro Lett."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"674","DOI":"10.1016\/j.nanoen.2019.05.082","article-title":"Skin-contact actuated single-electrode protein triboelectric nanogenerator and strain sensor for biomechanical energy harvesting and motion sensing","volume":"62","author":"Gogurla","year":"2019","journal-title":"Nano Energy"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"eaba9624","DOI":"10.1126\/sciadv.aba9624","article-title":"A breathable, biodegradable, antibacterial, and self-powered electronic skin based on all-nanofiber triboelectric nanogenerators","volume":"6","author":"Peng","year":"2020","journal-title":"Sci. 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