{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,25]],"date-time":"2026-03-25T02:22:36Z","timestamp":1774405356289,"version":"3.50.1"},"reference-count":63,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2019,5,25]],"date-time":"2019-05-25T00:00:00Z","timestamp":1558742400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001729","name":"Stiftelsen f\u00f6r\u00a0Strategisk Forskning","doi-asserted-by":"publisher","award":["GMT14-0077"],"award-info":[{"award-number":["GMT14-0077"]}],"id":[{"id":"10.13039\/501100001729","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001729","name":"Stiftelsen f\u00f6r\u00a0Strategisk Forskning","doi-asserted-by":"publisher","award":["RMA15-024"],"award-info":[{"award-number":["RMA15-024"]}],"id":[{"id":"10.13039\/501100001729","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>In this work, we investigated the sensing performance of epitaxial graphene on Si-face 4H-SiC (EG\/SiC) for liquid-phase detection of heavy metals (e.g., Pb and Cd), showing fast and stable response and low detection limit. The sensing platform proposed includes 3D-printed microfluidic devices, which incorporate all features required to connect and execute lab-on-chip (LOC) functions. The obtained results indicate that EG exhibits excellent sensing activity towards Pb and Cd ions. Several concentrations of Pb2+ solutions, ranging from 125 nM to 500 \u00b5M, were analyzed showing Langmuir correlation between signal and Pb2+ concentrations, good stability, and reproducibility over time. Upon the simultaneous presence of both metals, sensor response is dominated by Pb2+ rather than Cd2+ ions. To explain the sensing mechanisms and difference in adsorption behavior of Pb2+ and Cd2+ ions on EG in water-based solutions, we performed van-der-Waals (vdW)-corrected density functional theory (DFT) calculations and non-covalent interaction (NCI) analysis, extended charge decomposition analysis (ECDA), and topological analysis. We demonstrated that Pb2+ and Cd2+ ions act as electron-acceptors, enhancing hole conductivity of EG, due to charge transfer from graphene to metal ions, and Pb2+ ions have preferential ability to binding with graphene over cadmium. Electrochemical measurements confirmed the conductometric results, which additionally indicate that EG is more sensitive to lead than to cadmium.<\/jats:p>","DOI":"10.3390\/s19102393","type":"journal-article","created":{"date-parts":[[2019,5,26]],"date-time":"2019-05-26T23:07:27Z","timestamp":1558912047000},"page":"2393","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":34,"title":["Epitaxial Graphene Sensors Combined with 3D-Printed Microfluidic Chip for Heavy Metals Detection"],"prefix":"10.3390","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-0540-1965","authenticated-orcid":false,"given":"Maria Francesca","family":"Santangelo","sequence":"first","affiliation":[{"name":"Applied Sensors Science, Department of Physics, Chemistry, and Biology-IFM, Link\u00f6ping University, S-58183 Link\u00f6ping, Sweden"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8685-3332","authenticated-orcid":false,"given":"Ivan","family":"Shtepliuk","sequence":"additional","affiliation":[{"name":"Semiconductor Materials, Department of Physics, Chemistry, and Biology-IFM, Link\u00f6ping University, S-58183 Link\u00f6ping, Sweden"}]},{"given":"Daniel","family":"Filippini","sequence":"additional","affiliation":[{"name":"Optical Devices Laboratory, Department of Physics, Chemistry, and Biology-IFM, Link\u00f6ping University, S-58183 Link\u00f6ping, Sweden"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0646-5266","authenticated-orcid":false,"given":"Donatella","family":"Puglisi","sequence":"additional","affiliation":[{"name":"Applied Sensors Science, Department of Physics, Chemistry, and Biology-IFM, Link\u00f6ping University, S-58183 Link\u00f6ping, Sweden"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8478-4663","authenticated-orcid":false,"given":"Mikhail","family":"Vagin","sequence":"additional","affiliation":[{"name":"Division of Physics and Electronics, Department of Science and Technology, Physics and Electronics-ITN, Link\u00f6ping University, SE-58183 Link\u00f6ping, Sweden"}]},{"given":"Rositsa","family":"Yakimova","sequence":"additional","affiliation":[{"name":"Semiconductor Materials, Department of Physics, Chemistry, and Biology-IFM, Link\u00f6ping University, S-58183 Link\u00f6ping, Sweden"}]},{"given":"Jens","family":"Eriksson","sequence":"additional","affiliation":[{"name":"Applied Sensors Science, Department of Physics, Chemistry, and Biology-IFM, Link\u00f6ping University, S-58183 Link\u00f6ping, Sweden"}]}],"member":"1968","published-online":{"date-parts":[[2019,5,25]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"276","DOI":"10.1016\/j.bios.2014.07.052","article-title":"Electrochemical sensing of heavy metal ions with inorganic, organic and bio-materials","volume":"63","author":"Cui","year":"2015","journal-title":"Biosens. 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