{"id":529,"date":"2017-02-06T13:50:17","date_gmt":"2017-02-06T18:50:17","guid":{"rendered":"https:\/\/cbe.ncsu.edu\/velevgroup\/?page_id=529"},"modified":"2026-04-15T10:10:50","modified_gmt":"2026-04-15T14:10:50","slug":"han","status":"publish","type":"page","link":"https:\/\/cbe.ncsu.edu\/velevgroup\/members\/han\/","title":{"rendered":"Koohee Han"},"content":{"rendered":"\n
PhD, Chemical Engineering, 2018
North Carolina State University

M.S. Chemical Engineering, 2013
North Carolina State University

B.S. Chemical Engineering, 2011
University of Seoul, Seoul Korea

Curriculum Vitae<\/a> <\/td>
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Research Focus: Field-Driven Assembly of Anisotropic Patchy Particles for Soft Microbotics<\/strong><\/p>\n\n\n\n

We have shown earlier how metallo-dielectric Janus\/patchy spheres and microcubes, acquire complex polarization pattern in electrical and magnetic fields, leading to multidirectional interactions. We present a novel approach for assembling metallo-dielectric microcubes into soft robotic components, which may find applications in fields such as microscale manufacturing and active microfluidics. Their potential is illustrated in a preliminary way by making motile, reconfigurable and self-folding chains from patchy microcubes, which possess repeated bending motions when actuated by an external magnetic field. The residual polarization of the metal-coated facets leads to directional forces between the neighboring particles and between the particles and the field. The dipole-dipole and field-dipole interactions lead to dynamic reconfiguration. Depending on the cube-to-cube binding conformations the assembled chains have distinct responses to the external field. In the case of cis-conformation, the junction between two cubes can be actuated reversibly by a pulsating magnetic field, whereas in the trans-conformation cube-to-cube overlap makes the junction rigid and thus restricts the bending of the chain. Consequently, the sequence of cis- and trans conformations in the chain determines how the chain will respond and fold in a field and after it is turned off. We also seek to establish fundamental understanding and identify means of control of the chain dynamics. On this basis we design and demonstrate a microbot prototype capable of grabbing and transporting target objects.<\/p>\n\n\n

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Figure 1:<\/em> Capture and transportation of a cell by a microbot prototype.<\/p>\n\n\n\n

Publications<\/strong><\/p>\n\n\n\n

Han, K.; Shields, C.W., IV; Diwakar, N.M.; Bharti, B.; L\u00f3pez, G.P.; Velev, O.D. Sequence-encoded colloidal origami and microbot assemblies from patchy magnetic cubes. Science Advances<\/i> 2017.<\/strong> DOI: 10.1126\/sciadv.1701108.<\/a><\/p>\n\n\n\n

Bharti, B.; Rutkowski, D.; Han, K.; Kumar, A.U.; Hall, C.K.; Velev, O.D. Capillary Bridging as a Tool for Assembling Discrete Clusters of Patchy Particles. Journal of the American Chemical Society<\/em> 2016<\/strong>, 138 (45)<\/em>, 14948-14953.<\/a><\/p>\n\n\n\n

News Reports<\/strong><\/p>\n\n\n\n

C&E News\u00a0(ACS<\/em>) –\u00a0“Magnetic fields cause microcubes to respond like mini robots”<\/a><\/p>\n\n\n\n

NC State Press release<\/em> – “Microbot origami can capture, transport single cells”<\/a><\/p>\n\n\n\n

WIRED<\/em> – “Watch a micro ‘Pac-man’ capture a live cell”<\/a><\/p>\n\n\n\n

TechCrunch<\/em> – “These tiny modular ‘microbots’ can change shape to capture single cells”<\/a><\/p>\n\n\n\n

Phys.org<\/em> –“Microbot origami can capture, transport single cells”<\/a><\/p>\n\n\n\n

ScienceDaily<\/em> – “Microbot origami can capture, transport single cells”<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"

PhD, Chemical Engineering, 2018North Carolina State University M.S. Chemical Engineering, 2013North Carolina State University B.S. Chemical Engineering, 2011University of Seoul, Seoul Korea Curriculum Vitae Research…<\/p>\n","protected":false},"author":145,"featured_media":0,"parent":36,"menu_order":17,"comment_status":"closed","ping_status":"closed","template":"page-left.php","meta":{"_acf_changed":false,"first_name":[],"_exactmetrics_skip_tracking":false,"_exactmetrics_sitenote_active":false,"_exactmetrics_sitenote_note":"","_exactmetrics_sitenote_category":0,"footnotes":""},"class_list":["post-529","page","type-page","status-publish","hentry"],"acf":[],"_links":{"self":[{"href":"https:\/\/cbe.ncsu.edu\/velevgroup\/wp-json\/wp\/v2\/pages\/529","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/cbe.ncsu.edu\/velevgroup\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/cbe.ncsu.edu\/velevgroup\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/cbe.ncsu.edu\/velevgroup\/wp-json\/wp\/v2\/users\/145"}],"replies":[{"embeddable":true,"href":"https:\/\/cbe.ncsu.edu\/velevgroup\/wp-json\/wp\/v2\/comments?post=529"}],"version-history":[{"count":7,"href":"https:\/\/cbe.ncsu.edu\/velevgroup\/wp-json\/wp\/v2\/pages\/529\/revisions"}],"predecessor-version":[{"id":2862,"href":"https:\/\/cbe.ncsu.edu\/velevgroup\/wp-json\/wp\/v2\/pages\/529\/revisions\/2862"}],"up":[{"embeddable":true,"href":"https:\/\/cbe.ncsu.edu\/velevgroup\/wp-json\/wp\/v2\/pages\/36"}],"wp:attachment":[{"href":"https:\/\/cbe.ncsu.edu\/velevgroup\/wp-json\/wp\/v2\/media?parent=529"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}