US researchers have used the paper folding art of origami to construct 3D microfluidic devices created by a single-step photolithographic process.

Hong Liu and Richard Crooks, University of Texas at Austin, USA, have made a microfluidic device on a single sheet of flat paper that can quickly be folded by hand into its three-dimensional, multilayered working form. They tested the device in chemical analysis by demonstrating its utility in colorimetric and fluorescence assays. After the analysis is complete the device is simply unfolded to reveal each layer, and so the test results.

The single-step approach avoids the complications of sequential layer-by-layer photolithographic fabrication as well as requiring no tools nor special alignment techniques.

• Three-Dimensional Paper Microfluidic Devices Assembled Using the Principles of Origami
  H. Liu, R. M. Crooks,
  J. Am. Chem. Soc. 2011.
  DOI: 10.1021/ja2071779