{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T12:27:52Z","timestamp":1785414472501,"version":"3.56.0"},"reference-count":38,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2026,5,8]],"date-time":"2026-05-08T00:00:00Z","timestamp":1778198400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"JSPS International Research Fellow"},{"name":"Overseas Postdoctoral Talent Recruitment Program"},{"name":"JUST Scientific Research Staring Foundation","award":["1022932303"],"award-info":[{"award-number":["1022932303"]}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["52575210"],"award-info":[{"award-number":["52575210"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"award":["52575210"],"award-info":[{"award-number":["52575210"]}],"id":[{"id":"https:\/\/ror.org\/01h0zpd94","id-type":"ROR","asserted-by":"publisher"}]},{"name":"The Suqian Science and Technology Project","award":["K20251"],"award-info":[{"award-number":["K20251"]}]},{"name":"The Equipment Research and Development Projects of The Chinese Academy of Sciences","award":["PTYQ2024YZ0010"],"award-info":[{"award-number":["PTYQ2024YZ0010"]}]},{"name":"The Equipment Research and Development Projects of The Chinese Academy of Sciences","award":["PTYQ2024BJ0007"],"award-info":[{"award-number":["PTYQ2024BJ0007"]}]},{"DOI":"10.13039\/501100005308","name":"Amada Foundation","doi-asserted-by":"crossref","id":[{"id":"10.13039\/501100005308","id-type":"DOI","asserted-by":"crossref"}]},{"id":[{"id":"https:\/\/ror.org\/02qqez544","id-type":"ROR","asserted-by":"publisher"}]},{"name":"Grant-in-Aid for Scientific Research","award":["26K01366"],"award-info":[{"award-number":["26K01366"]}]},{"DOI":"10.13039\/100009088","name":"NSG Foundation","doi-asserted-by":"crossref","id":[{"id":"10.13039\/100009088","id-type":"DOI","asserted-by":"crossref"}]},{"DOI":"10.13039\/501100008656","name":"Iketani Science and Technology Foundation","doi-asserted-by":"crossref","id":[{"id":"10.13039\/501100008656","id-type":"DOI","asserted-by":"crossref"}]},{"id":[{"id":"https:\/\/ror.org\/0382jhd52","id-type":"ROR","asserted-by":"publisher"}]},{"DOI":"10.13039\/100015641","name":"Tateisi Science and Technology Foundation","doi-asserted-by":"crossref","id":[{"id":"10.13039\/100015641","id-type":"DOI","asserted-by":"crossref"}]},{"id":[{"id":"https:\/\/ror.org\/03myan165","id-type":"ROR","asserted-by":"publisher"}]},{"name":"JSPS Core-to-Core program","award":["JPJSCCA20190007"],"award-info":[{"award-number":["JPJSCCA20190007"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Biosensors"],"abstract":"<jats:p>In this study, we present a novel microfluidic platform for tunable size-based particle separation within a straight microchannel using symmetrical viscoelastic sheath flows. The device incorporates two pairs of symmetrical microchannels for sheath fluid injection: the first pair facilitates particle focusing and separation, while the second pair enables dynamic regulation of the separation distance between particle streams. Experimental results demonstrate that a 50 ppm polyethylene oxide (PEO) solution focuses 1 \u03bcm polystyrene particles toward the channel centerline via elastic forces, whereas 5 \u03bcm particles migrate toward the channel sidewalls under dominant inertial forces, effectively overcoming the elastic effects. The interplay between inertial and elastic forces thus achieves size-dependent particle separation. Furthermore, by adjusting the flow rate of the PEO sheath in the second pair of microchannels, the separation distance between the two particle populations can be modulated in real time. Higher PEO concentrations (500 and 1000 ppm) exhibit enhanced capabilities to deflect particle flow streams. By contrast, the lower PEO concentrations like 50, 100 and 200 ppm are more versatile in adjusting the separation distance. The biological applicability of this platform is further demonstrated through the tunable separation of Escherichia coli (E. coli) and Chlorella vulgaris (C. vulgaris). This microfluidic device demonstrates significant potential for downstream particle processing applications, including real-time particle detection and targeted drug delivery.<\/jats:p>","DOI":"10.3390\/bios16050273","type":"journal-article","created":{"date-parts":[[2026,5,11]],"date-time":"2026-05-11T19:35:43Z","timestamp":1778528143000},"page":"273","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Tunable Particle Separation in a Straight Microchannel via Symmetrical Viscoelastic Sheath Flows"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0009-0000-5876-313X","authenticated-orcid":false,"given":"Tianyuan","family":"Zhou","sequence":"first","affiliation":[{"name":"College of Mechanical Engineering, Jiangsu University of Science and Technology, Zhenjiang 212100, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Qi","family":"Cui","sequence":"additional","affiliation":[{"name":"College of Mechanical Engineering, Jiangsu University of Science and Technology, Zhenjiang 212100, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Guizhong","family":"Tian","sequence":"additional","affiliation":[{"name":"College of Mechanical Engineering, Jiangsu University of Science and Technology, Zhenjiang 212100, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jing","family":"Xia","sequence":"additional","affiliation":[{"name":"College of Mechanical Engineering, Jiangsu University of Science and Technology, Zhenjiang 212100, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ping","family":"Liu","sequence":"additional","affiliation":[{"name":"School of Mechanical and Electrical Engineering, Suqian University, Suqian 223800, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yoichiroh","family":"Hosokawa","sequence":"additional","affiliation":[{"name":"Medilux Research Center, Nara Institute of Science and Technology, Nara 630-0192, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0569-6740","authenticated-orcid":false,"given":"Yaxiaer","family":"Yalikun","sequence":"additional","affiliation":[{"name":"Medilux Research Center, Nara Institute of Science and Technology, Nara 630-0192, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pan","family":"Wang","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Transducer Technology, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai 200050, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2560-2417","authenticated-orcid":false,"given":"Shilun","family":"Feng","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Transducer Technology, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai 200050, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9499-3303","authenticated-orcid":false,"given":"Tianlong","family":"Zhang","sequence":"additional","affiliation":[{"name":"College of Mechanical Engineering, Jiangsu University of Science and Technology, Zhenjiang 212100, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,5,8]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"113","DOI":"10.1038\/s41378-020-00218-x","article-title":"Viscoelastic microfluidics: Progress and challenges","volume":"6","author":"Zhou","year":"2020","journal-title":"Microsyst. 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