Capillary Origami Inspired Fabrication of Complex 3D Hydrogel Constructs

• Published in: Small (Weinheim an der Bergstrasse, Germany) Vol. 12; no. 33; pp. 4492 - 4500
• Main Authors: Li, Moxiao, Yang, Qingzhen, Liu, Hao, Qiu, Mushu, Lu, Tian Jian, Xu, Feng
• Format: Journal Article
• Language: English
• Published: Germany Blackwell Publishing Ltd 01.09.2016; Wiley Subscription Services, Inc
• Subjects: capillary origami; Construction; Crosslinking; Dimethylpolysiloxanes - chemistry; Droplets; elastocapillary phenomena; Evaporation; Hydrogel, Polyethylene Glycol Dimethacrylate - chemistry; Hydrogels; Imaging, Three-Dimensional; Mathematical models; Membranes; Models, Theoretical; Nanotechnology; programmable fabrication; tailored geometric structures; Three dimensional models; Tissue Engineering - methods; Tissue Scaffolds - chemistry; tailored geometric structures; hydrogels; elastocapillary phenomena; programmable fabrication; capillary origami
• ISSN: 1613-6810; 1613-6829
• DOI: 10.1002/smll.201601147

Hydrogels have found broad applications in various engineering and biomedical fields, where the shape and size of hydrogels can profoundly influence their functions. Although numerous methods have been developed to tailor 3D hydrogel structures, it is still challenging to fabricate complex 3D hydrogel constructs. Inspired by the capillary origami phenomenon where surface tension of a droplet on an elastic membrane can induce spontaneous folding of the membrane into 3D structures along with droplet evaporation, a facile strategy is established for the fabrication of complex 3D hydrogel constructs with programmable shapes and sizes by crosslinking hydrogels during the folding process. A mathematical model is further proposed to predict the temporal structure evolution of the folded 3D hydrogel constructs. Using this model, precise control is achieved over the 3D shapes (e.g., pyramid, pentahedron, and cube) and sizes (ranging from hundreds of micrometers to millimeters) through tuning membrane shape, dimensionless parameter of the process (elastocapillary number Ce), and evaporation time. This work would be favorable to multiple areas, such as flexible electronics, tissue regeneration, and drug delivery. A facile method for fabrication of complex 3D hydrogel constructs is developed. Built upon capillary origami, well‐controlled hydrogel structures with programmable shapes and sizes are produced. The profiles of the structure are dependent on crosslinking time, properties of the membrane and liquid, and the membrane shape. This method holds great potential for various materials.