Bio-Inspired Synthetic Network. A Tissue-Like Printed Material

ORIGINAL: Nature

Vol. 340 no. 6128 pp. 48-52 

DOI: 10.1126/science.1229495

5 April 2013: 

Gabriel Villar, Alexander D. Graham, Hagan Bayley*

Department of Chemistry, University of Oxford, Oxford OX1 3TA, UK.

E-mail: hagan.bayley@chem.ox.ac.uk

A network of picoliter aqueous droplets generated by 3D printing. After printing, the droplet network folded into a hollow sphere (diameter: 0.4 millimeters). In these designed tissue-like materials, adjacent compartments are separated by lipid bilayers and can communicate with each other and the environment. Such printed materials might be used to deliver drugs or, in the long term, to augment failing organs. See page 48. Photo: Gabriel Villar

Collective behavior comes through the ability of neighboring objects to communicate and interact with each other. Villar et al. (p. 48; see the cover) produced three-dimensionally patterned, interconnected networks of lipid-bounded structures functionalized with transmembrane proteins, which allowed electrical communication along specific pathways.

Living cells communicate and cooperate to produce the emergent properties of tissues. Synthetic mimics of cells, such as liposomes, are typically incapable of cooperation and therefore cannot readily display sophisticated collective behavior. We printed tens of thousands of picoliter aqueous droplets that become joined by single lipid bilayers to form a cohesive material with cooperating compartments. Three-dimensional structures can be built with heterologous droplets in software-defined arrangements. The droplet networks can be functionalized with membrane proteins; for example, to allow rapid electrical communication along a specific path. The networks can also be programmed by osmolarity gradients to fold into otherwise unattainable designed structures. Printed droplet networks might be interfaced with tissues, used as tissue engineering substrates, or developed as mimics of living tissue.