{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T01:21:56Z","timestamp":1760059316603,"version":"build-2065373602"},"reference-count":37,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2025,6,4]],"date-time":"2025-06-04T00:00:00Z","timestamp":1748995200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100011033","name":"Agencia Estatal de Investigaci\u00f3n (AEI) and Fondo Europeo de Desarrollo Regional (FEDER)","doi-asserted-by":"publisher","award":["AGL2016-80643-R"],"award-info":[{"award-number":["AGL2016-80643-R"]}],"id":[{"id":"10.13039\/501100011033","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Gastroesophageal reflux disease (GERD) is a widespread condition that requires reliable and non-invasive diagnostic methods to minimize patient discomfort. This study presents a radiofrequency spectrophotometry sensor specifically designed to detect esophageal liquid flow and ionicity in real time without disrupting the patient\u2019s daily life. The sensor operates by measuring dielectric properties and ionic conductivity through the thoracic plexus, eliminating the need for invasive probes or prolonged monitoring. A study conducted on 49 participants demonstrated the sensor\u2019s ability to differentiate between various liquid media and identify beta dispersion relaxation as a biomarker for esophageal tissue damage, a key indicator of GERD progression. Additionally, alpha dispersion conductivity effectively distinguished reflux episodes, proving the sensor\u2019s high sensitivity. Unlike traditional diagnostic techniques such as endoscopy or pH monitoring, this radiofrequency spectrophotometry sensor enables continuous, real-time reflux detection, allowing patients to maintain a normal lifestyle during assessment. The results validate its potential as an innovative alternative for GERD diagnosis and monitoring, with future research focused on clinical validation, optimization, and integration into long-term patient monitoring systems.<\/jats:p>","DOI":"10.3390\/s25113533","type":"journal-article","created":{"date-parts":[[2025,6,4]],"date-time":"2025-06-04T06:00:49Z","timestamp":1749016849000},"page":"3533","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Design and Application of a Radiofrequency Spectrophotometry Sensor for Measuring Esophageal Liquid Flow to Detect Gastroesophageal Reflux"],"prefix":"10.3390","volume":"25","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9666-276X","authenticated-orcid":false,"given":"Pedro J.","family":"Fito","sequence":"first","affiliation":[{"name":"Instituto Universitario de Ingenier\u00eda de Alimentos FoodUPV, Universitat Polit\u00e8cnica de Val\u00e8ncia, Camino de Vera s\/n, 46022 Valencia, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0704-4906","authenticated-orcid":false,"given":"Ricardo J.","family":"Colom","sequence":"additional","affiliation":[{"name":"Instituto de Instrumentaci\u00f3n para Imagen Molecular I3M, Universitat Polit\u00e8cnica de Val\u00e8ncia, Camino de Vera s\/n, 46022 Valencia, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2857-8667","authenticated-orcid":false,"given":"Rafael","family":"Gadea-Girones","sequence":"additional","affiliation":[{"name":"Instituto de Instrumentaci\u00f3n para Imagen Molecular I3M, Universitat Polit\u00e8cnica de Val\u00e8ncia, Camino de Vera s\/n, 46022 Valencia, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6554-3231","authenticated-orcid":false,"given":"Jose M.","family":"Monzo","sequence":"additional","affiliation":[{"name":"Instituto de Instrumentaci\u00f3n para Imagen Molecular I3M, Universitat Polit\u00e8cnica de Val\u00e8ncia, Camino de Vera s\/n, 46022 Valencia, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Angel","family":"Tebar-Ruiz","sequence":"additional","affiliation":[{"name":"Instituto de Instrumentaci\u00f3n para Imagen Molecular I3M, Universitat Polit\u00e8cnica de Val\u00e8ncia, Camino de Vera s\/n, 46022 Valencia, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9341-8160","authenticated-orcid":false,"given":"F. Javier","family":"Puertas","sequence":"additional","affiliation":[{"name":"Neurophysiology and Sleep Unit, La Ribera University Hospital-FISABIO, 46600 Alzira, Spain"},{"name":"Faculty of Medicine and Health Sciences, Catholic University of Valencia \u201cSan Vicente M\u00e1rtir\u201d, 46001 Valencia, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9360-6869","authenticated-orcid":false,"given":"Marta","family":"Castro-Giraldez","sequence":"additional","affiliation":[{"name":"Instituto Universitario de Ingenier\u00eda de Alimentos FoodUPV, Universitat Polit\u00e8cnica de Val\u00e8ncia, Camino de Vera s\/n, 46022 Valencia, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,6,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1900","DOI":"10.1111\/j.1572-0241.2006.00630.x","article-title":"The Montreal Definition and Classification of Gastroesophageal Reflux Disease: A Global Evidence-Based Consensus","volume":"101","author":"Vakil","year":"2006","journal-title":"Off. 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