{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,24]],"date-time":"2026-03-24T07:53:18Z","timestamp":1774338798326,"version":"3.50.1"},"reference-count":27,"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>In this study, a micro-viscometer is developed for measuring shear-varying blood viscosity over a wide-ranging shear rate. The micro-viscometer consists of 10 microfluidic channel arrays, each of which has a different micro-channel width. The proposed design enables the retrieval of 10 different shear rates from a single flow rate, thereby enabling the measurement of shear-varying blood viscosity with a fixed flow rate condition. For this purpose, an optimal design that guarantees accurate viscosity measurement is selected from a parametric study. The functionality of the micro-viscometer is verified by both numerical and experimental studies. The proposed micro-viscometer shows 6.8% (numerical) and 5.3% (experimental) in relative error when compared to the result from a standard rotational viscometer. Moreover, a reliability test is performed by repeated measurement (N = 7), and the result shows 2.69 \u00b1 2.19% for the mean relative error. Accurate viscosity measurements are performed on blood samples with variations in the hematocrit (35%, 45%, and 55%), which significantly influences blood viscosity. Since the blood viscosity correlated with various physical parameters of the blood, the micro-viscometer is anticipated to be a significant advancement for realization of blood on a chip.<\/jats:p>","DOI":"10.3390\/s17061442","type":"journal-article","created":{"date-parts":[[2017,6,20]],"date-time":"2017-06-20T10:15:38Z","timestamp":1497953738000},"page":"1442","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":43,"title":["Micro-Viscometer for Measuring Shear-Varying Blood Viscosity over a Wide-Ranging Shear Rate"],"prefix":"10.3390","volume":"17","author":[{"given":"Byung","family":"Kim","sequence":"first","affiliation":[{"name":"Department of Biomedical Science and Engineering, Gwangju Institute of Science and Technology, Gwangju 61005, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Seung","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Biomedical Science and Engineering, Gwangju Institute of Science and Technology, Gwangju 61005, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Solkeun","family":"Jee","sequence":"additional","affiliation":[{"name":"School of Mechanical Engineering, Gwangju Institute of Science and Technology, Gwangju 61005, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Arslan","family":"Atajanov","sequence":"additional","affiliation":[{"name":"School of Mechanical Engineering, Gwangju Institute of Science and Technology, Gwangju 61005, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sung","family":"Yang","sequence":"additional","affiliation":[{"name":"Department of Biomedical Science and Engineering, Gwangju Institute of Science and Technology, Gwangju 61005, Korea"},{"name":"School of Mechanical Engineering, Gwangju Institute of Science and Technology, Gwangju 61005, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2017,6,20]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1195","DOI":"10.1016\/0002-9343(81)90827-5","article-title":"Direct relationship between blood pressure and blood viscosity in normal and hypertensive subjects","volume":"70","author":"Letcher","year":"1981","journal-title":"Am. 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