Systems Chemistry at the Nanoscale: Controlled fusion of polymer nanoparticles

Abstract: Particle fusion is key for combining the properties of multiple biological components. For example, cell fusion plays a crucial role in infection, muscle formation and tissue repair.1 The ability to direct analogous co-assembly between populations of synthetic nanoparticles also provides access to hybrid materials. Typically, this relies on incorporating complementary recognition units onto particle surfaces to thermodynamically favour co-assembly.2 Here I present a fundamentally different approach, where kinetically controlled hetero-fusion occurs between two populations of unfunctionalised polymer nanoparticles.3,4 Fusion extent can be tuned simply by adjusting polymer length. We probed fusion using an elemental tag for cryogenic scanning transmission electron microscopy combined with electron energy loss spectroscopy (cryo-STEM-EELS). Our results demonstrate emergence of a complex process when populations of synthetic nanoparticles are combined. We anticipate systems-level behaviour that results from such hetero-fusion will be fashioned as an elementary mechanism of synthetic communication that enables future technologies.

References

1. McNew, J. A. et al. Compartmental specificity of cellular membrane fusion encoded in SNARE proteins. Nature 407, 153–159 (2000).

2. Fan, Y. et al. Co-assembly of Synthetic Particles with Heterogenous Components. Chem. Mater. 36, 4011–4033 (2024).

3. Fielden, S. D. P., Derry, M. J., Miller, A. J., Topham, P. D. & O'Reilly, R. K. Triggered Polymersome Fusion. J. Am. Chem. Soc. 145, 5824–5833 (2023).

4. Fielden, S. D. P. Kinetically Controlled and Nonequilibrium Assembly of Block Copolymers in Solution. J. Am. Chem. Soc. 146, 18781–18796 (2024).

materials chemistrynanoscienceorganic chemistryphysical chemistrysupramolecular chemistryadaptation and self-organizing systems

Audience: researchers in the topic

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Systems Chemistry Discussion Series

Series comments: In the past decade, systems chemistry has emerged as a field for studying complex chemical systems akin to life. Systems chemistry is interdisciplinary by nature, with inspirations from various fields including biology, physics and computer science. However, the researchers from different backgrounds tend to lack common "language" to communicate with, as well as common goals to pursue as a field.

In this discussion series, we discuss variety of topics about systems chemistry, such as Brownian ratchet mechanisms, feedback-controlled systems, nonequilibrium thermodynamics, adaptive materials, supramolecular assemblies etc.. We aim at bridging the gaps between the different subfields by free, in-depth discussions on each topic. The discussion is held every 1-2 months. On each occasion, a speaker will give a presentation (20-30 min), followed by discussion (1-1.5 h).

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