Dynamic actuation of glassy polymersomes through isomerization of a single azobenzene unit at the block copolymer interface

  • Nature Chemistryvolume 10pages659666 (2018)
  • doi:10.1038/s41557-018-0027-6
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Nature has engineered exquisitely responsive systems where molecular-scale information is transferred across an interface and propagated over long length scales. Such systems rely on multiple interacting, signalling and adaptable molecular and supramolecular networks that are built on dynamic, non-equilibrium structures. Comparable synthetic systems are still in their infancy. Here, we demonstrate that the light-induced actuation of a molecularly thin interfacial layer, assembled from a hydrophilic- azobenzene -hydrophobic diblock copolymer, can result in a reversible, long-lived perturbation of a robust glassy membrane across a range of over 500 chemical bonds. We show that the out-of-equilibrium actuation is caused by the photochemical trans–cis isomerization of the azo group, a single chemical functionality, in the middle of the interfacial layer. The principles proposed here are implemented in water-dispersed nanocapsules, and have implications for on-demand release of embedded cargo molecules.

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The authors thank the US Army Research Office for funding through the MURI program (W911NF-15-1-0568).

Author information

Author notes

  1. These authors contributed equally: Mijanur Rahaman Molla, Poornima Rangadurai and Lucas Antony


  1. Department of Chemistry, University of Massachusetts, Amherst, MA, USA

    • Mijanur Rahaman Molla
    • , Poornima Rangadurai
    • , Subramani Swaminathan
    •  & S. Thayumanavan
  2. Institute for Molecular Engineering, University of Chicago, Chicago, IL, USA

    • Lucas Antony
    •  & Juan J. de Pablo
  3. Molecular and Cellular Biology Program, University of Massachusetts, Amherst, MA, USA

    • S. Thayumanavan
  4. Center for Bioactive Delivery, Institute for Applied Life Sciences, University of Massachusetts, Amherst, MA, USA

    • S. Thayumanavan


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S.T. conceived and supervised the project. M.R.M. initiated the project. M.R.M. and P.R. performed all the experiments, with help from S.S. J.d.P. initiated the simulations and computational studies. L.A. performed all the simulation studies. All authors contributed to the discussion of the results and preparation of the manuscript.

Corresponding author

Correspondence to S. Thayumanavan.

Supplementary information

  1. Supplementary information

    Supplementary synthesis and characterization details and analysis, Schemes 1–3, and Figures 1–16