{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,1]],"date-time":"2026-03-01T00:54:39Z","timestamp":1772326479414,"version":"3.50.1"},"reference-count":19,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2013,3,14]],"date-time":"2013-03-14T00:00:00Z","timestamp":1363219200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Micromachines"],"abstract":"<jats:p>We present a continuous-flow active micromixer based on channel-wall deflection in a polydimethylsiloxane (PDMS) chip for volume flows in the range up to 2 \u03bcL s\u22121 which is intended as a novel unit operation for the microfluidic Braille pin actuated platform. The chip design comprises a main microchannel connected to a series of side channels with dead ends aligned on the Braille pins. Computer-controlled deflection of the side-channel walls induces chaotic advection in the main-channel, which substantially accelerates mixing in low-Reynolds number flow. Sufficient mixing (mixing index MI below 0.1) of volume flows up to 0.5 \u03bcL s\u22121 could be achieved within residence times  ~500 ms in the micromixer. As an application, continuous dilution of a yeast cell sample by a ratio down to 1:10 was successfully demonstrated. The mixer is intended to serve as a component of bio-analytical devices or as a unit operation in the microfluidic Braille pin actuated platform.<\/jats:p>","DOI":"10.3390\/mi4010080","type":"journal-article","created":{"date-parts":[[2013,3,14]],"date-time":"2013-03-14T12:22:04Z","timestamp":1363263724000},"page":"80-89","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":41,"title":["Active Continuous-Flow Micromixer Using an External Braille Pin Actuator Array"],"prefix":"10.3390","volume":"4","author":[{"given":"Yawar","family":"Abbas","sequence":"first","affiliation":[{"name":"Laboratory for MEMS Applications, Department of Microsystems Engineering, IMTEK, University of Freiburg, Georges-Koehler-Allee 103, 79110 Freiburg, Germany"},{"name":"BIOS-Lab on chip group, MESA+ Institution of Nanotechnology, University of Twente, 7522 NH Enschede, The Netherlands"}]},{"given":"Junichi","family":"Miwa","sequence":"additional","affiliation":[{"name":"Laboratory for MEMS Applications, Department of Microsystems Engineering, IMTEK, University of Freiburg, Georges-Koehler-Allee 103, 79110 Freiburg, Germany"}]},{"given":"Roland","family":"Zengerle","sequence":"additional","affiliation":[{"name":"Laboratory for MEMS Applications, Department of Microsystems Engineering, IMTEK, University of Freiburg, Georges-Koehler-Allee 103, 79110 Freiburg, Germany"},{"name":"HSG-IMIT, Institut f\u00fcr Mikro- und Informationstechnik, Georges-Koehler-Allee 103, 79110 Freiburg, Germany"},{"name":"BIOSS\u2014Centre for Biological Signalling Studies, University Freiburg, 79104 Freiburg, Germany"}]},{"given":"Felix","family":"Von Stetten","sequence":"additional","affiliation":[{"name":"Laboratory for MEMS Applications, Department of Microsystems Engineering, IMTEK, University of Freiburg, Georges-Koehler-Allee 103, 79110 Freiburg, Germany"},{"name":"HSG-IMIT, Institut f\u00fcr Mikro- und Informationstechnik, Georges-Koehler-Allee 103, 79110 Freiburg, Germany"}]}],"member":"1968","published-online":{"date-parts":[[2013,3,14]]},"reference":[{"key":"ref_1","unstructured":"Nguyen, N.-T. 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Biotechnol."}],"container-title":["Micromachines"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2072-666X\/4\/1\/80\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T21:45:33Z","timestamp":1760219133000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2072-666X\/4\/1\/80"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2013,3,14]]},"references-count":19,"journal-issue":{"issue":"1","published-online":{"date-parts":[[2013,3]]}},"alternative-id":["mi4010080"],"URL":"https:\/\/doi.org\/10.3390\/mi4010080","relation":{},"ISSN":["2072-666X"],"issn-type":[{"value":"2072-666X","type":"electronic"}],"subject":[],"published":{"date-parts":[[2013,3,14]]}}}