Fluid interfacial energy drives the emergence of three-dimensional periodic structures in micropillar scaffolds

• Published in: Nature physics Vol. 17; no. 7; pp. 794 - 800
• Main Authors: Yasuga, Hiroki, Iseri, Emre, Wei, Xi, Kaya, Kerem, Di Dio, Giacomo, Osaki, Toshihisa, Kamiya, Koki, Nikolakopoulou, Polyxeni, Buchmann, Sebastian, Sundin, Johan, Bagheri, Shervin, Takeuchi, Shoji, Herland, Anna, Miki, Norihisa, van der Wijngaart, Wouter
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 2021; Nature Publishing Group
• Subjects: 142/126; 639/301; 639/301/1023; 639/301/119; 639/301/923; 639/766/189; Actuator materials; Atomic; Building materials; Catalysis; Cellular structure; Chemical synthesis; Classical and Continuum Physics; Complex Systems; Composite materials; Condensed Matter Physics; Construction materials; Contact angle; Energy; Fluids; Glycerol; Interfacial energy; Letter; Liquid surfaces; Mathematical and Computational Physics; Medicin och hälsovetenskap; Mineral oils; Molecular; Optical and Plasma Physics; Periodic structures; Photonic crystals; Physics; Physics and Astronomy; Scaffolds; Simulation; Theoretical; Tissues
• ISSN: 1745-2473; 1745-2481; 1745-2481
• DOI: 10.1038/s41567-021-01204-4

Structures that are periodic on a microscale in three dimensions are abundant in nature, for example, in the cellular arrays that make up living tissue. Such structures can also be engineered, appearing in smart materials 1 – 4 , photonic crystals 5 , chemical reactors 6 , and medical 7 and biomimetic 8 technologies. Here we report that fluid–fluid interfacial energy drives three-dimensional (3D) structure emergence in a micropillar scaffold. This finding offers a rapid and scalable way of transforming a simple pillar scaffold into an intricate 3D structure that is periodic on a microscale, comprising a solid microscaffold, a dispersed fluid and a continuous fluid. Structures generated with this technique exhibit a set of unique features, including a stationary internal liquid–liquid interface. Using this approach, we create structures with an internal liquid surface in a regime of interest for liquid–liquid catalysis. We also synthesize soft composites in solid, liquid and gas combinations that have previously not been shown, including actuator materials with temperature-tunable microscale pores. We further demonstrate the potential of this method for constructing 3D materials that mimic tissue with an unprecedented level of control, and for microencapsulating human cells at densities that address an unresolved challenge in cell therapy. The revelation that fluid–fluid interfacial energy can drive structure formation in micropillar scaffolds offers a scalable way of synthesizing soft composites, which may have applications in building materials that mimic biological tissue.