{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,18]],"date-time":"2026-01-18T13:24:17Z","timestamp":1768742657755,"version":"3.49.0"},"reference-count":29,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2017,5,20]],"date-time":"2017-05-20T00:00:00Z","timestamp":1495238400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>We present here an electrochemical sensor microsystem for the monitoring of pH. The all-polymeric device is comprised of a cyclic olefin copolymer substrate, a 200 nm-thin patterned layer of conductive polymer (PEDOT), and a 70 nm electropolymerized layer of a pH sensitive conductive polymer (polyaniline). The patterning of the fluidic (microfluidic channels) and conductive (wiring and electrodes) functional elements was achieved with a single soft PDMS mold via a single embossing step process. A post-processing treatment with ethylene glycol assured the functional enhancement of the electrodes, as demonstrated via an electrical and electrochemical characterization. A surface modification of the electrodes was carried out, based on voltammetric electropolymerization, to obtain a thin layer of polyaniline. The mechanism for pH sensing is based on the redox reactions of the polyaniline layer caused by protonation. The sensing performance of the microsystem was finally validated by monitoring its potentiometric response upon exposure to a relevant range of pH.<\/jats:p>","DOI":"10.3390\/s17051169","type":"journal-article","created":{"date-parts":[[2017,5,23]],"date-time":"2017-05-23T01:47:33Z","timestamp":1495504053000},"page":"1169","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":16,"title":["Fully-Polymeric pH Sensor Realized by Means of a Single-Step Soft Embossing Technique"],"prefix":"10.3390","volume":"17","author":[{"given":"Paola","family":"Fanzio","sequence":"first","affiliation":[{"name":"Department of Precision and Microsystems Engineering (PME), Delft University of Technology, 2628 CD Delft, The Netherlands"}]},{"given":"Chi-Tung","family":"Chang","sequence":"additional","affiliation":[{"name":"Department of Precision and Microsystems Engineering (PME), Delft University of Technology, 2628 CD Delft, The Netherlands"}]},{"given":"Maciej","family":"Skolimowski","sequence":"additional","affiliation":[{"name":"Micronit Microtechnologies B.V., 7521 PV Enschede, The Netherlands"}]},{"given":"Simone","family":"Tanzi","sequence":"additional","affiliation":[{"name":"Micronit Microtechnologies B.V., 7521 PV Enschede, The Netherlands"}]},{"given":"Luigi","family":"Sasso","sequence":"additional","affiliation":[{"name":"Department of Precision and Microsystems Engineering (PME), Delft University of Technology, 2628 CD Delft, The Netherlands"}]}],"member":"1968","published-online":{"date-parts":[[2017,5,20]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"3027","DOI":"10.3390\/s7123027","article-title":"Review on state-of-the-art in polymer based pH sensors","volume":"7","author":"Korostynska","year":"2007","journal-title":"Sensors"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"7216","DOI":"10.1021\/acsnano.6b04005","article-title":"A Wearable Electrochemical Platform for Noninvasive Simultaneous Monitoring of Ca2+ and pH","volume":"10","author":"Nyein","year":"2016","journal-title":"ACS Nano."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"509","DOI":"10.1038\/nature16521","article-title":"Fully integrated wearable sensor arrays for multiplexed in situ perspiration analysis","volume":"529","author":"Gao","year":"2016","journal-title":"Nature"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"123","DOI":"10.1039\/C2AN36422K","article-title":"Tattoo-based potentiometric ion-selective sensors for epidermal pH monitoring","volume":"138","author":"Bandodkar","year":"2013","journal-title":"Analyst"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"566","DOI":"10.1038\/nnano.2016.38","article-title":"A graphene-based electrochemical device with thermoresponsive microneedles for diabetes monitoring and therapy","volume":"11","author":"Lee","year":"2016","journal-title":"Nat. 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