{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,14]],"date-time":"2025-10-14T07:00:13Z","timestamp":1760425213848,"version":"build-2065373602"},"reference-count":23,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2013,6,21]],"date-time":"2013-06-21T00:00:00Z","timestamp":1371772800000},"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>In this study, we developed a microfluidic chip with a magnetically driven microrobot for oocyte enucleation. A microfluidic system was specially designed for enucleation, and the microrobot actively controls the local flow-speed distribution in the microfluidic chip. The microrobot can adjust fluid resistances in a channel and can open or close the channel to control the flow distribution. Analytical modeling was conducted to control the fluid speed distribution using the microrobot, and the model was experimentally validated. The novelties of the developed microfluidic system are as follows: (1) the cutting speed improved significantly owing to the local fluid flow control; (2) the cutting volume of the oocyte can be adjusted so that the oocyte undergoes less damage; and (3) the nucleus can be removed properly using the combination of a microrobot and hydrodynamic forces. Using this device, we achieved a minimally invasive enucleation process. The average enucleation time was 2.5 s and the average removal volume ratio was 20%. The proposed new system has the advantages of better operation speed, greater cutting precision, and potential for repeatable enucleation.<\/jats:p>","DOI":"10.3390\/mi4020272","type":"journal-article","created":{"date-parts":[[2013,6,21]],"date-time":"2013-06-21T14:35:28Z","timestamp":1371825328000},"page":"272-285","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":39,"title":["On-Chip Enucleation of Bovine Oocytes using  Microrobot-Assisted Flow-Speed Control"],"prefix":"10.3390","volume":"4","author":[{"given":"Lin","family":"Feng","sequence":"first","affiliation":[{"name":"Department of Micro-Nano Systems Engineering, Graduate School of Engineering, Nagoya University, 1 Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan"}]},{"given":"Masaya","family":"Hagiwara","sequence":"additional","affiliation":[{"name":"Department of Aerospace and Mechanical Engineering, University of California, Los Angeles, CA 90095, USA"}]},{"given":"Akihiko","family":"Ichikawa","sequence":"additional","affiliation":[{"name":"Department of Micro-Nano Systems Engineering, Graduate School of Engineering, Nagoya University, 1 Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2508-1615","authenticated-orcid":false,"given":"Fumihito","family":"Arai","sequence":"additional","affiliation":[{"name":"Department of Micro-Nano Systems Engineering, Graduate School of Engineering, Nagoya University, 1 Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan"}]}],"member":"1968","published-online":{"date-parts":[[2013,6,21]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"992","DOI":"10.1016\/j.theriogenology.2005.09.012","article-title":"After Dolly\u2014Ethical limits to the use of biotechnology on farm animals","volume":"65","author":"Lassen","year":"2005","journal-title":"Theriogenology"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"113","DOI":"10.1034\/j.1600-0897.2003.00064.x","article-title":"Cloning adult farm animals: A review of the possibilities and problems associated with somatic cell nuclear transfer","volume":"50","author":"Edwards","year":"2003","journal-title":"Am. 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[4th ed.]."}],"container-title":["Micromachines"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2072-666X\/4\/2\/272\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T21:47:29Z","timestamp":1760219249000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2072-666X\/4\/2\/272"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2013,6,21]]},"references-count":23,"journal-issue":{"issue":"2","published-online":{"date-parts":[[2013,6]]}},"alternative-id":["mi4020272"],"URL":"https:\/\/doi.org\/10.3390\/mi4020272","relation":{},"ISSN":["2072-666X"],"issn-type":[{"type":"electronic","value":"2072-666X"}],"subject":[],"published":{"date-parts":[[2013,6,21]]}}}