{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,5]],"date-time":"2026-01-05T15:16:09Z","timestamp":1767626169823,"version":"build-2065373602"},"reference-count":52,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2018,9,22]],"date-time":"2018-09-22T00:00:00Z","timestamp":1537574400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100005799","name":"National Chiao Tung University","doi-asserted-by":"publisher","award":["106W970, 107W970"],"award-info":[{"award-number":["106W970, 107W970"]}],"id":[{"id":"10.13039\/501100005799","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Veterans General Hospitals and University System of Taiwan Joint Research Program","award":["VGHUST106-G5-3-4"],"award-info":[{"award-number":["VGHUST106-G5-3-4"]}]},{"name":"Ministry of Science and Technology","award":["MOST 105-2628-B-009-001-MY3, MOST 106-2633-B-009-001"],"award-info":[{"award-number":["MOST 105-2628-B-009-001-MY3, MOST 106-2633-B-009-001"]}]},{"name":"National Taiwan University Hospital, Hsin-Chu branch","award":["107-HCH057"],"award-info":[{"award-number":["107-HCH057"]}]},{"name":"Basic Research Award, Asia-Pacific La Roche-Posay Foundation","award":["2014"],"award-info":[{"award-number":["2014"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Diabetes has become a chronic metabolic disorder, and the growing diabetes population makes medical care more important. We investigated using a portable and noninvasive contact lens as an ideal sensor for diabetes patients whose tear fluid contains glucose. The key feature is the reversible covalent interaction between boronic acid and glucose, which can provide a noninvasive glucose sensor for diabetes patients. We present a phenylboronic acid (PBA)-based HEMA contact lens that exhibits a reversible swelling\/shrinking effect to change its thickness. The difference in thickness can be detected in a picture taken with a smartphone and analyzed using software. Our novel technique offers the following capabilities: (i) non-enzymatic and continuous glucose detection with the contact lens; (ii) no need for an embedded circuit and power source for the glucose sensor; and (iii) the use of a smartphone to detect the change in thickness of the contact lens with no need for additional photo-sensors. This technique is promising for a noninvasive measurement of the glucose level and simple implementation of glucose sensing with a smartphone.<\/jats:p>","DOI":"10.3390\/s18103208","type":"journal-article","created":{"date-parts":[[2018,9,24]],"date-time":"2018-09-24T10:38:49Z","timestamp":1537785529000},"page":"3208","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":78,"title":["Noninvasive Glucose Monitoring with a Contact Lens and Smartphone"],"prefix":"10.3390","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7815-5913","authenticated-orcid":false,"given":"You-Rong","family":"Lin","sequence":"first","affiliation":[{"name":"Institute of Biomedical Engineering, College of Electrical and Computer Engineering, National Chiao Tung University, Hsinchu 300, Taiwan"},{"name":"Department of Electrical and Computer Engineering, College of Electrical and Computer Engineering, National Chiao Tung University, Hsinchu 30010, Taiwan"}]},{"given":"Chin-Chi","family":"Hung","sequence":"additional","affiliation":[{"name":"Institute of Biomedical Engineering, College of Electrical and Computer Engineering, National Chiao Tung University, Hsinchu 300, Taiwan"}]},{"given":"Hsien-Yi","family":"Chiu","sequence":"additional","affiliation":[{"name":"Department of Dermatology, National Taiwan University Hospital Hsin-Chu Branch, Hsinchu 30059, Taiwan"},{"name":"Institute of Biomedical Engineering, College of Medicine and College of Engineering, National Taiwan University, Taipei 10051, Taiwan"},{"name":"Department of Dermatology, National Taiwan University Hospital, Taipei 10002, Taiwan"},{"name":"Department of Dermatology, College of Medicine, National Taiwan University, Taipei 10051, Taiwan"}]},{"given":"Po-Han","family":"Chang","sequence":"additional","affiliation":[{"name":"Department of Applied Chemistry, National Chiao Tung University, Hsinchu 30010, Taiwan"}]},{"given":"Bor-Ran","family":"Li","sequence":"additional","affiliation":[{"name":"Institute of Biomedical Engineering, College of Electrical and Computer Engineering, National Chiao Tung University, Hsinchu 300, Taiwan"},{"name":"Department of Applied Chemistry, National Chiao Tung University, Hsinchu 30010, Taiwan"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5993-1473","authenticated-orcid":false,"given":"Sheng-Jen","family":"Cheng","sequence":"additional","affiliation":[{"name":"Institute of Biomedical Engineering, College of Electrical and Computer Engineering, National Chiao Tung University, Hsinchu 300, Taiwan"},{"name":"Department of Electrical and Computer Engineering, College of Electrical and Computer Engineering, National Chiao Tung University, Hsinchu 30010, Taiwan"}]},{"given":"Jia-Wei","family":"Yang","sequence":"additional","affiliation":[{"name":"Institute of Biomedical Engineering, College of Electrical and Computer Engineering, National Chiao Tung University, Hsinchu 300, Taiwan"},{"name":"Department of Electrical and Computer Engineering, College of Electrical and Computer Engineering, National Chiao Tung University, Hsinchu 30010, Taiwan"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1270-3961","authenticated-orcid":false,"given":"Shien-Fong","family":"Lin","sequence":"additional","affiliation":[{"name":"Institute of Biomedical Engineering, College of Electrical and Computer Engineering, National Chiao Tung University, Hsinchu 300, Taiwan"},{"name":"Department of Electrical and Computer Engineering, College of Electrical and Computer Engineering, National Chiao Tung University, Hsinchu 30010, Taiwan"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3443-7943","authenticated-orcid":false,"given":"Guan-Yu","family":"Chen","sequence":"additional","affiliation":[{"name":"Institute of Biomedical Engineering, College of Electrical and Computer Engineering, National Chiao Tung University, Hsinchu 300, Taiwan"},{"name":"Department of Biological Science and Technology, National Chiao Tung University, Hsinchu 30010, Taiwan"}]}],"member":"1968","published-online":{"date-parts":[[2018,9,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"97","DOI":"10.2337\/diaclin.33.2.97","article-title":"Standards of medical care in diabetes\u20142015 abridged for primary care providers","volume":"33","author":"Association","year":"2015","journal-title":"Clin. 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