Article | Published:

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

Nature Chemistryvolume 10pages659666 (2018) | Download Citation


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.

Access optionsAccess options

Rent or Buy article

Get time limited or full article access on ReadCube.


All prices are NET prices.

Additional information

Publisher’s note: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Change history

  • 28 June 2018

    In the version of this Article originally published, multiple changes to the “Results and discussion” section were required. In paragraph 1, “(Supplementary Fig. 1)” should have read “(Fig. 1e–j and Supplementary Fig. 1)”; in the first sentence of paragraph 3, “(R6G)” should have read “(R6G, Fig. 2i)”; in paragraph 6 in the sentence beginning “Temporal release of hydrophilic...”, Supplementary Fig. 4 should have been cited after “360 nm”; in paragraph 9, in the sentence beginning “To test this...”, “Fig. 4e” should have read “Fig. 4a”; in paragraph 10, in the sentence beginning “When the irradiation...”, “(Fig. 4a–d)” should have read “(Fig. 4d,e)”; in paragraph 11, in the sentence beginning “Pristine PLA”, “P1” should have read “P2”; and in the penultimate paragraph, in the sentence beginning “Moreover, a control PEG-PLA...”, “block copolymer” should have been followed by (P5); Fig. 4g should have been Fig. 4c; “hydrophobic azobenzene small molecules” should have been followed by (12); and Fig. 4f should have been Fig. 4b. Finally, Supplementary Videos 1 and 2 were missing from the Article. All of these corrections have been made to the online versions.


  1. 1.

    Natansohn, A. & Rochon, P. Photoinduced motions in azobenzene-based amorphous polymers: possible photonic devices. Adv. Mater. 11, 1387–1391 (1999).

  2. 2.

    Yamada, M. et al. Photomobile polymer materials: towards light-driven plastic motors. Angew. Chem. Int. Ed. 47, 4986–4988 (2008).

  3. 3.

    Swallen, S. F. et al. Organic glasses with exceptional thermodynamic and kinetic stability. Science 315, 353–356 (2007).

  4. 4.

    Singh, S., Ediger, M. D. & de Pablo, J. J. Ultrastable glasses from in silico vapour deposition. Nat. Mater. 12, 139–144 (2013).

  5. 5.

    Dalal, S. S., Walters, D. M., Lyubimov, I., de Pablo, J. J. & Ediger, M. D. Tunable molecular orientation and elevated thermal stability of vapor-deposited organic semiconductors. Proc. Natl Acad. Sci. USA 112, 4227–4232 2015).

  6. 6.

    Bin, Y., Xia, T., Patrick, A. & Yue, Z. Light responsive block co-polymer vesicles based on a photo softening effect. Soft Matter 7, 10001–10009 (2011).

  7. 7.

    Gelebart, A. H. et al. Making waves in a photoactive polymer film. Nature 546, 632–636 (2017).

  8. 8.

    Dong, R., Zhu, B., Zhou, Y., Yana, D. & Zhu, X. Reversible photoisomerization of azobenzene containing polymeric systems driven by visible light. Polym. Chem. 4, 912–915 2013).

  9. 9.

    Wang, G., Tong, X. & Zhao, Y. Preparation of azobenzene-containing amphiphilic diblock copolymers for light-responsive micellar aggregates. Macromolecules 37, 8911–8917 (2004).

  10. 10.

    Liu, X. & Jiang, M. Optical switching of self-assembly: micellization and micelle–hollow-sphere transition of hydrogen-bonded polymers. Angew. Chem. Int. Ed. 45, 3846–3850 (2006).

  11. 11.

    Feng, Z., Lin, L., Yan, Z. & Yu, Y. Dual responsive block copolymer micelles functionalized by NIPAM and azobenzene. Macromol. Rapid Commun. 31, 640–644 (2010).

  12. 12.

    Kuiper, J. M. & Engberts, B. F. N. H-aggregation of azobenzene substituted amphiphiles in vesicular membranes. Langmuir 20, 1152–1160 (2004).

  13. 13.

    Pencer, J. & Hallett, F. R. Effects of vesicle size and shape on static and dynamic light scattering measurements. Langmuir 19, 7488–7497 (2003).

  14. 14.

    O’Reilly, R. K., Hawker, C. J. & Wooley, K. L. Cross-linked block copolymer micelles: functional nanostructures of great potential and versatility. Chem. Soc. Rev. 35, 1068–1083 (2006).

  15. 15.

    Lee, S. M., Chen, H., Dettmer, C. M., O’Halloran, T. V. & Nguyen, S. T. Polymer-caged lipsome: pH-responsive delivery system with high stability. J. Am. Chem. Soc. 129, 15096–15097 (2007).

  16. 16.

    Savariar, E. N., Aathimanikandan, S. V. & Thayumanavan, S. Supramolecular assemblies from amphiphilic homopolymers: testing the scope. J. Am. Chem. Soc. 128, 16224–16230 (2006).

  17. 17.

    Beharry, A. A. & Woolley, G. A. Azobenzene photoswitches for biomolecules. Chem. Soc. Rev. 40, 4422–4437 (2011).

  18. 18.

    Merino, E. & Ribagorda, M. Control over molecular motion using the cistrans photoisomerization of the azo group. Beilstein J. Org. Chem. 8, 1071–1090 (2012).

  19. 19.

    Gabor, G. & Fischer, E. Spectra and cistrans isomerism in highly bipolar derivatives of azobenzene. J. Phys. Chem. 75, 581–583 (1971).

  20. 20.

    Bandara, H. M. D. & Burdette, S. C. Photoisomerization in different classes of azobenzene. Chem. Soc. Rev. 41, 1809–1825 (2012).

  21. 21.

    Fialkowski, M. et al. Principles and implementations of dissipative (dynamic) self-assembly. J. Phys. Chem. B 110, 2482–2496 (2006).

  22. 22.

    Boekhoven, J. et al. Dissipative self-assembly of a molecular gelator by using a chemical fuel. Angew. Chem. Int. Ed. 49, 4825–4828 (2010).

  23. 23.

    Mattia, E. & Otto, S. Supramolecular systems chemistry. Nat. Nanotech. 10, 111–119 (2015).

  24. 24.

    Natansohn, A. & Rochon, P. Photoinduced motions in azo-containing polymers. Chem. Rev. 102, 4139–4175 (2002).

  25. 25.

    Marder, S. R. et al Large 1st hyperpolarizabilities in push–pull polyenes by tuning of the bond-length alteration and aromaticity. Science 263, 511–514 1994).

  26. 26.

    Jorgensen, W. L., Maxwell, D. S. & Tirado-Rives, J. Development and testing of the OPLS all atom force field on conformational energetics and properties of organic liquids. J. Am. Chem. Soc. 118, 11225–11236 (1996).

  27. 27.

    Kaminski, G. A., Friesner, R. A., Tirado-Rives, J. & Jorgensen, W. L. Evaluation and reparametrization of the OPLS-AA force field for proteins via comparison with accurate quantum chemical calculations on peptides. J. Phys. Chem. B 105, 6474–6487 (2001).

  28. 28.

    Dorgan, J. R., Lehermeier, H. & Mang, M. Thermal and rheological properties of commercial-grade poly(lactic acid). J. Polym. Environ. 8, 1–9 (2000).

  29. 29.

    Auras, R., Harte, B. & Selke, S. An overview of polylactides as packaging materials. Macromol. Biosci. 4, 835–864 (2004).

  30. 30.

    Younes, H. & Cohn, D. Phase separation in poly(ethyleneglycol)/poly(lactic acid) blends. Eur. Polym. J. 24, 765–773 (1988).

  31. 31.

    Zhao, H. et al. Preparation and characterization of PEG/PLA multiblock and triblock copolymer. Bull. Korean Chem. Soc. 33, 1638–1642 (2012).

  32. 32.

    Fang, G. J. Athermal photofluidization of glasses. Nat. Commun. 4, 1–9 (2013).

  33. 33.

    Qiu, Y., Antony, L. W., de Pablo, J. J. & Ediger, M. D. Photostability can be significantly modulated by molecular packing in glasses. J. Am. Chem. Soc. 138, 11282–11289 (2016).

Download references


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


  1. Search for Mijanur Rahaman Molla in:

  2. Search for Poornima Rangadurai in:

  3. Search for Lucas Antony in:

  4. Search for Subramani Swaminathan in:

  5. Search for Juan J. de Pablo in:

  6. Search for S. Thayumanavan in:


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

  2. Supplementary Movie 1

    Real-time movie showing that no reaction occurred between hexamathylene diamine encapsulated within the aqueous lumen of the supramolecular capsule formed by P2 and sebacoyl chloride dissolved in hexane.

  3. Supplementary Movie 2

    Real-time movie of nylon formation between hexamathylene released from the supramolecular capsule formed by P2 upon light irradiation and sebacoyl chloride dissolved in hexane.

About this article

Publication history