{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,11]],"date-time":"2025-11-11T13:10:32Z","timestamp":1762866632993,"version":"build-2065373602"},"reference-count":41,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2015,5,21]],"date-time":"2015-05-21T00:00:00Z","timestamp":1432166400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Micromachines"],"abstract":"<jats:p>This paper presents methods for the formation of hollow microcapsules and microlenses using multiphase microdroplets. Microdroplets, which consist of a gas core and an organic phase shell, were generated at a single junction on a silicon device without surface treatment of the fluidic channels. Droplet, core and shell dimensions were controlled by varying the flow rates of each phase. When the organic solvent was released from the organic phase shell, the environmental conditions changed the shape of the solidified polymer shell to either a hollow capsule or a microlens. A uniform solvent release process produced polymeric capsules with nanoliter gas core volumes and a membrane thickness of approximately 3 \u03bcm. Alternatively physical rearrangement of the core and shell allowed for the formation of polymeric microlenses. On-demand formation of the polymer lenses in wells and through-holes polydimethylsiloxane (PDMS) structures was achieved. Optical properties of the lenses were controlled by changing the dimension of these structures.<\/jats:p>","DOI":"10.3390\/mi6050622","type":"journal-article","created":{"date-parts":[[2015,5,21]],"date-time":"2015-05-21T10:30:59Z","timestamp":1432204259000},"page":"622-633","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Formation of Polymeric Hollow Microcapsules and Microlenses Using Gas-in-Organic-in-Water Droplets"],"prefix":"10.3390","volume":"6","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7180-4370","authenticated-orcid":false,"given":"Dong","family":"Yoon","sequence":"first","affiliation":[{"name":"Faculty of Science and Engineering, Waseda University, 3-4-1, Okubo, Shinjuku-ku, Tokyo 169-8555, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kenta","family":"Hasegawa","sequence":"additional","affiliation":[{"name":"Faculty of Science and Engineering, Waseda University, 3-4-1, Okubo, Shinjuku-ku, Tokyo 169-8555, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yuji","family":"Kaneko","sequence":"additional","affiliation":[{"name":"Faculty of Science and Engineering, Waseda University, 3-4-1, Okubo, Shinjuku-ku, Tokyo 169-8555, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Takahiro","family":"Arakawa","sequence":"additional","affiliation":[{"name":"Department of Biomedical Devices and Instrumentation, Tokyo Medical and Dental University,  2-3-10, Kanda-Surugadai, Chiyoda-ku, Tokyo 101-0062, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jeung","family":"Go","sequence":"additional","affiliation":[{"name":"School of Mechanical Engineering, Pusan National University, Busan 609-735, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tetsushi","family":"Sekiguchi","sequence":"additional","affiliation":[{"name":"Institute for Nanoscience and Nanotechnology, Waseda University, 513, Tsurumaki-cho, Waseda, Shinjuku-ku, Tokyo 162-0041, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Shuichi","family":"Shoji","sequence":"additional","affiliation":[{"name":"Faculty of Science and Engineering, Waseda University, 3-4-1, Okubo, Shinjuku-ku, Tokyo 169-8555, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2015,5,21]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"908","DOI":"10.1126\/science.6776628","article-title":"Microencapsulated islets as bioartificial endocrine pancreas","volume":"210","author":"Lim","year":"1980","journal-title":"Science"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"849","DOI":"10.1016\/S0142-9612(01)00191-0","article-title":"Multi-layered microcapsules for cell encapsulation","volume":"23","author":"Chia","year":"2002","journal-title":"Biomaterials"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"379","DOI":"10.1016\/j.bios.2014.08.059","article-title":"Droplet-based microfluidics for high-throughput screening of a metagenomic library for isolation of microbial enzymes","volume":"67","author":"Hosokawa","year":"2015","journal-title":"Biosensors Bioelectron."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"203","DOI":"10.1016\/j.jconrel.2009.01.005","article-title":"Bioactive cell-hydrogel microcapsules for cell-based drug delivery","volume":"135","author":"Orive","year":"2009","journal-title":"J. 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