{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,23]],"date-time":"2026-01-23T14:38:45Z","timestamp":1769179125441,"version":"3.49.0"},"reference-count":32,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2019,5,14]],"date-time":"2019-05-14T00:00:00Z","timestamp":1557792000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001858","name":"VINNOVA","doi-asserted-by":"publisher","award":["2016-01656, 2018-01679"],"award-info":[{"award-number":["2016-01656, 2018-01679"]}],"id":[{"id":"10.13039\/501100001858","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001729","name":"Stiftelsen f\u00f6r\u00a0Strategisk Forskning","doi-asserted-by":"publisher","award":["FID15-0129"],"award-info":[{"award-number":["FID15-0129"]}],"id":[{"id":"10.13039\/501100001729","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Generation of large areas of graphene possessing high quality and uniformity will be a critical factor if graphene-based devices\/sensors are to be commercialized. In this work, epitaxial graphene on a 2\" SiC wafer was used to fabricate sensors for the detection of illicit drugs (amphetamine or cocaine). The main target application is on-site forensic detection where there is a high demand for reliable and cost-efficient tools. The sensors were designed and processed with specially configured metal electrodes on the graphene surface by utilizing a series of anchors where the metal contacts are directly connected on the SiC substrate. This has been shown to improve adhesion of the electrodes and decrease the contact resistance. A microfluidic system was constructed to pump solutions over the defined graphene surface that could then act as a sensor area and react with the target drugs. Several prototypic systems were tested where non-covalent interactions were used to localize the sensing components (antibodies) within the measurement cell. The serendipitous discovery of a wavelength-dependent photoactivity for amphetamine and a range of its chemical analogs, however, limited the general application of these prototypic systems. The experimental results reveal that the drug molecules interact with the graphene in a molecule dependent manner based upon a balance of    \u03c0   -stacking interaction of the phenyl ring with graphene (p-doping) and the donation of the amine nitrogens lone pair electrons into the    \u03c0   -   \u03c0   *-system of graphene (n-doping).<\/jats:p>","DOI":"10.3390\/s19102214","type":"journal-article","created":{"date-parts":[[2019,5,14]],"date-time":"2019-05-14T10:42:33Z","timestamp":1557830553000},"page":"2214","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Chemical Sensors Generated on Wafer-Scale Epitaxial Graphene for Application to Front-Line Drug Detection"],"prefix":"10.3390","volume":"19","author":[{"given":"Mikael","family":"Karlsson","sequence":"first","affiliation":[{"name":"RISE Research Institutes of Sweden AB, Box 1070, SE-164 25 Kista, Sweden"},{"name":"Pamitus AB, Timotejv\u00e4gen 1, SE-352 53 V\u00e4xj\u00f6, Sweden"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Carl","family":"Strandqvist","sequence":"additional","affiliation":[{"name":"Swedish National Forensic Centre, SE-581 94 Link\u00f6ping, Sweden"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3606-8985","authenticated-orcid":false,"given":"Johnny","family":"Jussi","sequence":"additional","affiliation":[{"name":"RISE Research Institutes of Sweden AB, Box 1070, SE-164 25 Kista, Sweden"},{"name":"Department of Applied Physics, Royal Institute of Technology, Science for Life Laboratory, SE-171 21 Solna, Sweden"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Olof","family":"\u00d6berg","sequence":"additional","affiliation":[{"name":"RISE Research Institutes of Sweden AB, Box 1070, SE-164 25 Kista, Sweden"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5966-0204","authenticated-orcid":false,"given":"Ingemar","family":"Petermann","sequence":"additional","affiliation":[{"name":"RISE Research Institutes of Sweden AB, Box 1070, SE-164 25 Kista, Sweden"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Louise","family":"Elmlund","sequence":"additional","affiliation":[{"name":"Swedish National Forensic Centre, SE-581 94 Link\u00f6ping, Sweden"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Simon","family":"Dunne","sequence":"additional","affiliation":[{"name":"Swedish National Forensic Centre, SE-581 94 Link\u00f6ping, Sweden"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ying","family":"Fu","sequence":"additional","affiliation":[{"name":"Department of Applied Physics, Royal Institute of Technology, Science for Life Laboratory, SE-171 21 Solna, Sweden"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Qin","family":"Wang","sequence":"additional","affiliation":[{"name":"RISE Research Institutes of Sweden AB, Box 1070, SE-164 25 Kista, Sweden"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2019,5,14]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"197","DOI":"10.1038\/nature04233","article-title":"Two-dimensional gas of massless Dirac fermions in graphene","volume":"438","author":"Novoselov","year":"2005","journal-title":"Nature"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"109","DOI":"10.1103\/RevModPhys.81.109","article-title":"The electronic properties of graphene","volume":"81","author":"Guinea","year":"2009","journal-title":"Rev. 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