{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,17]],"date-time":"2025-10-17T13:51:18Z","timestamp":1760709078557,"version":"build-2065373602"},"reference-count":50,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2016,6,1]],"date-time":"2016-06-01T00:00:00Z","timestamp":1464739200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"NIH NIDCD","award":["K25DC008291"],"award-info":[{"award-number":["K25DC008291"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Micromachines"],"abstract":"<jats:p>Low flow rate micropumps play an increasingly important role in drug therapy research. Infusions to small biological structures and lab-on-a-chip applications require ultra-low flow rates and will benefit from the ability to expend no power in the blocked-flow state. Here we present a planar micropump based on gallium phase-change actuation that leverages expansion during solidification to occlude the flow channel in the off-power state. The presented four chamber peristaltic micropump was fabricated with a combination of Micro Electro Mechanical System (MEMS) techniques and additive manufacturing direct write technologies. The device is 7 mm \u00d7 13 mm \u00d7 1 mm (&lt;100 mm3) with the flow channel and exterior coated with biocompatible Parylene-C, critical for implantable applications. Controllable pump rates from 18 to 104 nL\/min were demonstrated, with 11.1 \u00b1 0.35 nL pumped per actuation at an efficiency of 11 mJ\/nL. The normally-closed state of the gallium actuator prevents flow and diffusion between the pump and the biological system or lab-on-a-chip, without consuming power. This is especially important for implanted applications with periodic drug delivery regimens.<\/jats:p>","DOI":"10.3390\/mi7060099","type":"journal-article","created":{"date-parts":[[2016,6,1]],"date-time":"2016-06-01T19:22:34Z","timestamp":1464808954000},"page":"99","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":23,"title":["Towards an Implantable, Low Flow Micropump That Uses No Power in the Blocked-Flow State"],"prefix":"10.3390","volume":"7","author":[{"given":"Dean","family":"Johnson","sequence":"first","affiliation":[{"name":"Rochester Institute of Technology, Microsystems Engineering, Rochester, NY 14623, USA"}]},{"given":"David","family":"Borkholder","sequence":"additional","affiliation":[{"name":"Rochester Institute of Technology, Microsystems Engineering, Rochester, NY 14623, USA"}]}],"member":"1968","published-online":{"date-parts":[[2016,6,1]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"E8","DOI":"10.3171\/2009.4.FOCUS0983","article-title":"In vivo performance of a microelectrode neural probe with integrated drug delivery","volume":"27","author":"Rohatgi","year":"2009","journal-title":"Neurosurg. 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