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Droplet networks with incorporated protein diodes show collective properties

Nature Nanotechnology volume 4, pages 437–440 (2009)Cite this article

Abstract

Recently, we demonstrated that submicrolitre aqueous droplets submerged in an apolar liquid containing lipid can be tightly connected by means of lipid bilayers1,2,3,4,5 to form networks4,5,6. Droplet interface bilayers have been used for rapid screening of membrane proteins7,8 and to form asymmetric bilayers with which to examine the fundamental properties of channels and pores9. Networks, meanwhile, have been used to form microscale batteries and to detect light4. Here, we develop an engineered protein pore with diode-like properties that can be incorporated into droplet interface bilayers in droplet networks to form devices with electrical properties including those of a current limiter, a half-wave rectifier and a full-wave rectifier. The droplet approach, which uses unsophisticated components (oil, lipid, salt water and a simple pore), can therefore be used to create multidroplet networks with collective properties that cannot be produced by droplet pairs.

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Figure 1: Droplet interface bilayer systems.
Figure 2: Rectification of the 7R–αHL pore.
Figure 3: Droplet networks containing WT–αHL and 7R–αHL pores.
Figure 4: Full-wave rectification in a four-droplet network.

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Acknowledgements

This work was funded by a Royal Society Wolfson Research Merit Award to H.B., the Medical Research Council and the National Institutes of Health. W.L.H. was supported by a Rhodes Scholarship.

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Authors and Affiliations

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

    Giovanni Maglia, Andrew J. Heron, Ellina Mikhailova, Qiuhong Li, Stephen Cheley & Hagan Bayley

  2. Division of Health Sciences and Technology, Harvard Medical School and Massachusetts Institute of Technology, Boston, 02115-5750, Massachusetts, USA

    William L. Hwang

  3. Department of Chemistry, University of Massachusetts, Amherst, 01003, Massachusetts, USA

    Matthew A. Holden

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  1. Giovanni Maglia
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  2. Andrew J. Heron
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  3. William L. Hwang
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  5. Ellina Mikhailova
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  6. Qiuhong Li
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  7. Stephen Cheley
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  8. Hagan Bayley
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Contributions

G.M. designed the protein diode and E.M., Q.L. and S.C. made the protein. G.M. performed the research on planar bilayers. W.L.H., A.J.H. and M.A.H. designed the DIB networks. A.J.H. and W.L.H. created and tested the DIB networks. G.M., A.J.H., W.L.H. and H.B. wrote the paper. H.B. directed the project.

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Correspondence to Hagan Bayley.

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Maglia, G., Heron, A., Hwang, W. et al. Droplet networks with incorporated protein diodes show collective properties. Nature Nanotech 4, 437–440 (2009). https://doi.org/10.1038/nnano.2009.121

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