posted on 2021-08-24, 21:15authored byYuanqing Zhu, Rong Fan, Zhiyuan Zheng, Zhiqiang Zhu, Ting Si, Ronald X. Xu
We
propose a compound interfacial shearing (CIS) process for versatile
production of monodisperse Janus emulsions with controllable structural
and topographic features. The process induces an active periodic force
to decouple material and process parameters, enables independent control
of compartmental features in Janus emulsions, and facilitates inline
and on-demand generation of various geometric features for a large
variety of process parameters and material properties. Janus emulsions
of poly(ethylene glycol) diacrylate (PEGDA) with a controlled number
of compartments are produced by CIS and photopolymerized to form micro-hydrogels
with designated interfacial curvatures. PEGDA micro-hydrogels can
be further modified to achieve anisotropy of surface or internal features
by the content of an oily dispersed phase. MCF-7 human breast cancer
cells are encapsulated in micro-hydrogels for cell proliferation with
satisfactory viability. By modifying PEGDA micro-hydrogels with RGDS-conjugated
polystyrene microspheres, we have demonstrated the controlled spatial
adhesion of MCF-7 cells and human umbilical vein endothelial cells
(HUVECs) on the substrates of different three-dimensional (3D) curvatures.
Our pilot study suggests a simple and potentially scalable approach
to produce 3D substrates with controllable structural and topographic
features for 3D guided cell organization.