{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,7]],"date-time":"2025-11-07T09:18:25Z","timestamp":1762507105028,"version":"build-2065373602"},"reference-count":26,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2017,6,20]],"date-time":"2017-06-20T00:00:00Z","timestamp":1497916800000},"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>Plasmonic nanostructures are widely used for various sensing applications by monitoring changes in refractive index through optical spectroscopy or as substrates for surface enhanced Raman spectroscopy. However, in most practical situations conventional surface plasmon resonance is preferred for biomolecular interaction analysis because of its high resolution in surface coverage and the simple single-material planar interface. Still, plasmonic nanostructures may find unique sensing applications, for instance when the nanoscale geometry itself is of interest. This calls for new methods to prepare nanoscale particles and cavities with controllable dimensions and curvature. In this work, we present two types of plasmonic nanopores where the solid support underneath a nanohole array has been etched, thereby creating cavities denoted as \u2018nanowells\u2019 or \u2018nanocaves\u2019 depending on the degree of anisotropy (dry or wet etch). The refractometric sensitivity is shown to be enhanced upon removing the solid support because of an increased probing volume and a shift of the asymmetric plasmonic field towards the liquid side of the finite gold film. Furthermore, the structures exhibit different spectral changes upon binding inside the cavities compared to the gold surface, which means that the structures can be used for location-specific detection. Other sensing applications are also suggested.<\/jats:p>","DOI":"10.3390\/s17061444","type":"journal-article","created":{"date-parts":[[2017,6,20]],"date-time":"2017-06-20T10:15:38Z","timestamp":1497953738000},"page":"1444","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["Fabrication and Characterization of Plasmonic Nanopores with Cavities in the Solid Support"],"prefix":"10.3390","volume":"17","author":[{"given":"Bita","family":"Malekian","sequence":"first","affiliation":[{"name":"Department of Chemistry and Chemical Engineering, Chalmers University of Technology, 41296 Gothenburg, Sweden"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kunli","family":"Xiong","sequence":"additional","affiliation":[{"name":"Department of Chemistry and Chemical Engineering, Chalmers University of Technology, 41296 Gothenburg, Sweden"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Gustav","family":"Emilsson","sequence":"additional","affiliation":[{"name":"Department of Chemistry and Chemical Engineering, Chalmers University of Technology, 41296 Gothenburg, Sweden"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jenny","family":"Andersson","sequence":"additional","affiliation":[{"name":"Insplorion AB, Sahlgrenska Science Park, Medicinaregatan 8A, 41390 Gothenburg, Sweden"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Cecilia","family":"Fager","sequence":"additional","affiliation":[{"name":"Department of Physics, Chalmers University of Technology, 41296 Gothenburg, Sweden"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Eva","family":"Olsson","sequence":"additional","affiliation":[{"name":"Department of Physics, Chalmers University of Technology, 41296 Gothenburg, Sweden"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Elin","family":"Larsson-Langhammer","sequence":"additional","affiliation":[{"name":"Insplorion AB, Sahlgrenska Science Park, Medicinaregatan 8A, 41390 Gothenburg, Sweden"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1545-5860","authenticated-orcid":false,"given":"Andreas","family":"Dahlin","sequence":"additional","affiliation":[{"name":"Department of Chemistry and Chemical Engineering, Chalmers University of Technology, 41296 Gothenburg, Sweden"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2017,6,20]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"123","DOI":"10.1515\/nanoph-2016-0101","article-title":"Recent advances in nanoplasmonic biosensors: Applications and lab-on-a-chip integration","volume":"6","author":"Lopez","year":"2017","journal-title":"Nanophotonics"},{"doi-asserted-by":"crossref","unstructured":"Jackman, J.A., Rahim Ferhan, A., and Cho, N.-J. 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