{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,2]],"date-time":"2026-06-02T12:35:58Z","timestamp":1780403758924,"version":"3.54.1"},"reference-count":33,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2020,6,25]],"date-time":"2020-06-25T00:00:00Z","timestamp":1593043200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"the start-up funds provided to R.E. by the Henry Samueli School of Engineering and the Department of Electrical Engineering at the University of California, Irvine.","award":["0000"],"award-info":[{"award-number":["0000"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Electrowetting on dielectric-based digital microfluidic platforms (EWOD-DMF) have a potential to impact point-of-care diagnostics. Conventionally, EWOD-DMF platforms are manufactured in cleanrooms by expert technicians using costly and time consuming micro-nanofabrication processes such as optical lithography, depositions and etching. However, such high-end microfabrication facilities are extremely challenging to establish in resource-poor and low-income countries, due to their high capital investment and operating costs. This makes the fabrication of EWOD-DMF platforms extremely challenging in low-income countries, where such platforms are most needed for many applications such as point-of-care testing applications. To address this challenge, we present a low-cost and simple fabrication procedure for EWOD-DMF electrode arrays, which can be performed anywhere with a commercial office inkjet printer without the need of expensive cleanroom facilities. We demonstrate the utility of our platform to move and mix droplets of different reagents and physiologically conductive buffers, thereby showing its capability to potentially perform a variety of biochemical assays. By combining our low-cost, inkjet-printed EWOD-DMF platform with smartphone imaging technology and a compact control system for droplet manipulation, we also demonstrate a portable and hand-held device which can be programmed to potentially perform a variety of biochemical assays.<\/jats:p>","DOI":"10.3390\/s20123593","type":"journal-article","created":{"date-parts":[[2020,6,25]],"date-time":"2020-06-25T10:36:54Z","timestamp":1593081414000},"page":"3593","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":37,"title":["A Low-Cost, Disposable and Portable Inkjet-Printed Biochip for the Developing World"],"prefix":"10.3390","volume":"20","author":[{"given":"Kushal","family":"Joshi","sequence":"first","affiliation":[{"name":"Department of Biomedical Engineering, University of California, Irvine, CA 92697, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Vanessa","family":"Velasco","sequence":"additional","affiliation":[{"name":"Biochemistry Department, Stanford University, Palo Alto, CA 92697, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rahim","family":"Esfandyarpour","sequence":"additional","affiliation":[{"name":"Department of Biomedical Engineering, University of California, Irvine, CA 92697, USA"},{"name":"Department of Electrical Engineering, University of California, Irvine, CA 92697, USA"},{"name":"Henry Samueli School of Engineering, University of California, Irvine, CA 92697, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2020,6,25]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"330","DOI":"10.1021\/ac002800y","article-title":"Lab-on-a-chip: A revolution in biological and medical sciences","volume":"72","author":"Figeys","year":"2000","journal-title":"Anal. 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