{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,9]],"date-time":"2026-05-09T10:54:56Z","timestamp":1778324096912,"version":"3.51.4"},"reference-count":26,"publisher":"MDPI AG","issue":"24","license":[{"start":{"date-parts":[[2019,12,13]],"date-time":"2019-12-13T00:00:00Z","timestamp":1576195200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003725","name":"National Research Foundation of Korea","doi-asserted-by":"publisher","award":["NRF-2018K2A9A1A01090496"],"award-info":[{"award-number":["NRF-2018K2A9A1A01090496"]}],"id":[{"id":"10.13039\/501100003725","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003725","name":"National Research Foundation of Korea","doi-asserted-by":"publisher","award":["2019R1F1A1059782"],"award-info":[{"award-number":["2019R1F1A1059782"]}],"id":[{"id":"10.13039\/501100003725","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100007029","name":"State Committee of Science","doi-asserted-by":"publisher","award":["18T-1C114"],"award-info":[{"award-number":["18T-1C114"]}],"id":[{"id":"10.13039\/501100007029","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>We developed a microwave glucose sensor based on the modified first-order Hilbert curve design and measured glucose concentration in aqueous solutions by using a real-time microwave near-field electromagnetic interaction technique. We observed S21 transmission parameters of the sensor at resonant frequencies depend on the glucose concentration. We could determine the glucose concentration in the 0\u2013250 mg\/dL concentration range at an operating frequency of near 6 GHz. The measured minimum detectable signal was 0.0156 dB\/(mg\/dL) and the measured minimum detectable concentration was 1.92 mg\/dL. The simulation result for the minimum detectable signal and the minimum detectable concentration was 0.0182 dB\/(mg\/dL) and 1.65 mg\/dL, respectively. The temperature instability of the sensor for human glycemia in situ measurement range (27\u201334 \u00b0C for fingers and 36\u201340 \u00b0C for body temperature ranges) can be improved by the integration of the temperature sensor in the microwave stripline platform and the obtained data can be corrected during signal processing. The microwave signal\u2013temperature dependence is almost linear with the same slope for a glucose concentration range of 50\u2013150 mg\/dL. The temperature correlation coefficient is 0.05 dB\/\u00b0C and 0.15 dB\/\u00b0C in 27\u201334 \u00b0C and 36\u201340 \u00b0C temperature range, respectively. The presented system has a cheap, easy fabrication process and has great potential for non-invasive glucose monitoring.<\/jats:p>","DOI":"10.3390\/s19245525","type":"journal-article","created":{"date-parts":[[2019,12,13]],"date-time":"2019-12-13T11:27:22Z","timestamp":1576236442000},"page":"5525","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":55,"title":["Real-Time Noninvasive Measurement of Glucose Concentration Using a Modified Hilbert Shaped Microwave Sensor"],"prefix":"10.3390","volume":"19","author":[{"given":"Levon","family":"Odabashyan","sequence":"first","affiliation":[{"name":"Department of Radiophysics, Yerevan State University, Yerevan 0025, Armenia"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9909-8321","authenticated-orcid":false,"given":"Arsen","family":"Babajanyan","sequence":"additional","affiliation":[{"name":"Department of Radiophysics, Yerevan State University, Yerevan 0025, Armenia"}]},{"given":"Zhirayr","family":"Baghdasaryan","sequence":"additional","affiliation":[{"name":"Department of Radiophysics, Yerevan State University, Yerevan 0025, Armenia"},{"name":"Department of Physics, Sogang University, Seoul 121-742, Korea"}]},{"given":"Seungwan","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Physics, Sogang University, Seoul 121-742, Korea"}]},{"given":"Jongchel","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Physics, Sogang University, Seoul 121-742, Korea"}]},{"given":"Barry","family":"Friedman","sequence":"additional","affiliation":[{"name":"Department of Physics, Sam Houston State University, Huntsville, TX 77341, USA"}]},{"given":"Jung-Ha","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Life Science, Sogang University, Seoul 121-742, Korea"}]},{"given":"Kiejin","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Physics, Sogang University, Seoul 121-742, Korea"}]}],"member":"1968","published-online":{"date-parts":[[2019,12,13]]},"reference":[{"key":"ref_1","unstructured":"(2019, November 12). 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