Self-folding micropatterned polymeric containers
We demonstrate self-folding of precisely patterned, optically transparent, all-polymeric containers and describe their utility in mammalian cell and microorganism encapsulation and culture. The polyhedral containers, with SU-8 faces and biodegradable polycaprolactone (PCL) hinges, spontaneously assembled on heating. Self-folding was driven by a minimization of surface area of the liquefying PCL hinges within lithographically patterned two-dimensional (2D) templates. The strategy allowed for the fabrication of containers with variable polyhedral shapes, sizes and precisely defined porosities in all three dimensions. We provide proof-of-concept for the use of these polymeric containers as encapsulants for beads, chemicals, mammalian cells and bacteria. We also compare accelerated hinge degradation rates in alkaline solutions of varying pH. These optically transparent containers resemble three-dimensional (3D) micro-Petri dishes and can be utilized to sustain, monitor and deliver living biological components.
KeywordsCell encapsulation therapy Tissue engineering Drug delivery Microcontainers Lithography Bio-MEMS
We acknowledge Christina Randall for providing the beta cells used in this study and Jatinder Randhawa for valuable discussions on self-assembly of larger-scale scaffolds. We also thank Madeline Cohn for her part in early experimental work with the polymeric containers. This research was supported by the NIH Director’s New Innovator Award Program, part of the NIH Roadmap for Medical Research, Grant No. 1-DP2-OD004346-01, DP2-OD004346-01S1, the Iacocca Family Foundation and the Camille & Henry Dreyfus Foundation.
- J.G. Fernandez, A. Khademhosseini, Adv. Mater. 22, 2538–2541 (2010)Google Scholar
- B. Gimi, D. Artemov, T. Leong, D.H. Gracias, W. Gilson, M. Stuber, Z.M. Bhujwalla, Cell Transplant. 16, 403–408 (2007)Google Scholar
- S. Kusuda, S. Sawano, S. Konishi, Presented at IEEE 20th International Conference on Micro Electro Mechanical Systems (MEMS), 21–25 January 2007Google Scholar
- S. Prakash, H. Soe-Lin, Trends Biomater. Artif. Organs 18, 24–35 (2004)Google Scholar
- G.E. Wnek, G.L. Bowlin, Encyclopedia of Biomaterials and Bioengineering, 2nd edn. (Informa Healthcare, London, 2008), pp. 8–31Google Scholar