{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,14]],"date-time":"2026-04-14T16:18:58Z","timestamp":1776183538286,"version":"3.50.1"},"reference-count":55,"publisher":"MDPI AG","issue":"14","license":[{"start":{"date-parts":[[2019,7,19]],"date-time":"2019-07-19T00:00:00Z","timestamp":1563494400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003741","name":"Instituci\u00f3 Catalana de Recerca i Estudis Avan\u00e7ats","doi-asserted-by":"publisher","award":["ICREA ACAMADEMIA 2018"],"award-info":[{"award-number":["ICREA ACAMADEMIA 2018"]}],"id":[{"id":"10.13039\/501100003741","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003329","name":"Ministerio de Econom\u00eda y Competitividad","doi-asserted-by":"publisher","award":["TEC2016-75650-R"],"award-info":[{"award-number":["TEC2016-75650-R"]}],"id":[{"id":"10.13039\/501100003329","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Ag\u00e8ncia de Gesti\u00f3 d\u2019Ajuts Universitaris i de Recerca","award":["2017SGR-1159"],"award-info":[{"award-number":["2017SGR-1159"]}]},{"DOI":"10.13039\/501100002809","name":"Generalitat de Catalunya","doi-asserted-by":"publisher","award":["2018FI_B_00111"],"award-info":[{"award-number":["2018FI_B_00111"]}],"id":[{"id":"10.13039\/501100002809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Ministerio de Ciencia Innovaci\u00f3n y Universidades","award":["IJCI-2017-31339"],"award-info":[{"award-number":["IJCI-2017-31339"]}]},{"name":"Universidad politecnica de Madrid Young Researchers Support Program","award":["VJIDOCUPM18MGB"],"award-info":[{"award-number":["VJIDOCUPM18MGB"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>A microstrip defect ground structure (DGS) based on a pair of dumbbell-shaped slots is used for sensing. The device is a differential sensor consisting of a pair of mirrored lines loaded with a dumbbell-shaped DGS, and the output variable is the cross-mode transmission coefficient. Such a variable is very sensitive to asymmetries in the line pair, e.g., caused by an asymmetric dielectric load in the dumbbell-shaped DGSs. Therefore, the sensor is of special interest for the dielectric characterization of solids and liquids, or for the measurement of variables related to complex permittivity changes. It is shown in this work that by adding fluidic channels on top of the dumbbell-shaped DGSs, the device is useful for liquid characterization, particularly for the measurement of solute concentration in very diluted solutions. A sensitivity analysis useful for sensor design is carried out in this paper.<\/jats:p>","DOI":"10.3390\/s19143189","type":"journal-article","created":{"date-parts":[[2019,7,22]],"date-time":"2019-07-22T02:55:37Z","timestamp":1563764137000},"page":"3189","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":63,"title":["Differential Microfluidic Sensors Based on Dumbbell-Shaped Defect Ground Structures in Microstrip Technology: Analysis, Optimization, and Applications"],"prefix":"10.3390","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6502-5987","authenticated-orcid":false,"given":"Paris","family":"V\u00e9lez","sequence":"first","affiliation":[{"name":"CIMITEC, Departament d\u2019Enginyeria Electr\u00f2nica, Universitat Aut\u00f2noma de Barcelona, 08193 Bellaterra, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1271-3801","authenticated-orcid":false,"given":"Jonathan","family":"Mu\u00f1oz-Enano","sequence":"additional","affiliation":[{"name":"CIMITEC, Departament d\u2019Enginyeria Electr\u00f2nica, Universitat Aut\u00f2noma de Barcelona, 08193 Bellaterra, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Marta","family":"Gil","sequence":"additional","affiliation":[{"name":"Departamento de Ingenieria Audiovisual y Comunicaciones, Universidad Polit\u00e9cnica de Madrid, 28031 Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6116-8681","authenticated-orcid":false,"given":"Javier","family":"Mata-Contreras","sequence":"additional","affiliation":[{"name":"Departamento de Ingenier\u00eda de Comunicaciones, Universidad de M\u00e1laga, 29016 M\u00e1laga, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1494-9167","authenticated-orcid":false,"given":"Ferran","family":"Mart\u00edn","sequence":"additional","affiliation":[{"name":"CIMITEC, Departament d\u2019Enginyeria Electr\u00f2nica, Universitat Aut\u00f2noma de Barcelona, 08193 Bellaterra, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2019,7,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"86","DOI":"10.1109\/22.899965","article-title":"A Design of the Lowpass Filter Using the Novel Microstrip Defected Ground Structure","volume":"49","author":"Ahn","year":"2001","journal-title":"IEEE Trans. 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