logo nano spa 1
  • Cabecera 1
    nanoscience and nanotechnology: small is different

Dissipative Self-assembly and Wall-less fluidics

Prof. Thomas M. Hermans
University of Strasbourg & CNRS
Martes, 14 Febrero 2023 12:00

Abstract

Our group works at the interface of supramolecular chemistry, systems chemistry, fluidics, and biomedical engineering. In this presentation, I will present two of our main research lines

  1. Dissipative Self-assembly: Living cells contain supramolecular polymers such as actin filaments and microtubules that use chemical fuels (ATP and GTP) to control where and when they form. The dissipation of the fuels allows such structures to be strong, but yet dynamic under non-equilibrium conditions. Here, I present a selection of recent1–4 synthetic systems where chemical fuels or light are used to control dissipative self-assembly. Interesting new behaviors were found, such as spontaneous supramolecular size oscillations, traveling polymerization, self-sorting, or transient (dis)assembly that are not possible under thermodynamic control.
  2. Wall-less fluidics: Microfluidics is hampered by solid wall interactions, leading to excessive pressure drop for small channels, solute adhesion, and fouling. Here I show how wall-less liquid tubes can be stabilized by permanent magnets.5–7 The flowing liquid is fully enclosed within a surrounding magnetic liquid leading to self-healing, uncloggable, and frictionless microfluidic channels. Common fluidic operations such as valving, mixing, and peristaltic pumping can be achieved by moving permanent magnets without physical contact with the tubes. This enables new types of flow chemistry and low-shear transport of fluids.

Keywords:self-assembly, nonequilibrium, supramolecular polymer, microfluidics, magnets

References:
(1) Leira-Iglesias, J.; Tassoni, A.; Adachi, T.; Stich, M.; Hermans, T. M. Oscillations, Travelling Fronts and Patterns in a
Supramolecular System. Nature Nanotechnology 2018, 13 (11), 1021. https://doi.org/10.1038/s41565-018-0270-4.
(2) Singh, N.; Lainer, B.; Formon, G. J. M.; De Piccoli, S.; Hermans, T. M. Re-Programming Hydrogel Properties Using a Fuel-Driven
Reaction Cycle. J. Am. Chem. Soc. 2020, 142 (9), 4083–4087. https://doi.org/10.1021/jacs.9b11503.
(3) Singh, N.; Lopez-Acosta, A.; Formon, G. J. M.; Hermans, T. M. Chemically Fueled Self-Sorted Hydrogels. J. Am. Chem. Soc. 2022,
144 (1), 410–415. https://doi.org/10.1021/jacs.1c10282.
(4) Sharko, A.; Livitz, D.; De Piccoli, S.; Bishop, K. J. M.; Hermans, T. M. Insights into Chemically Fueled Supramolecular Polymers.
Chem. Rev. 2022, 122 (13), 11759–11777. https://doi.org/10.1021/acs.chemrev.1c00958.
(5) Hermans, T.; Coey, J. M. D.; Dunne, P.; Doudin, B. Device and Method for Circulating Liquids. WO2018134360A1, July 26, 2018.
https://patents.google.com/patent/WO2018134360A1/en.
(6) Dunne, P.; Adachi, T.; Dev, A. A.; Sorrenti, A.; Giacchetti, L.; Bonnin, A.; Bourdon, C.; Mangin, P. H.; Coey, J. M. D.; Doudin, B.;
Hermans, T. M. Liquid Flow and Control without Solid Walls. Nature 2020, 581 (7806), 58–62. https://doi.org/10.1038/s41586-
020-2254-4.
(7) Dev, A. A.; Dunne, P.; Hermans, T. M.; Doudin, B. Fluid Drag Reduction by Magnetic Confinement. Langmuir 2022, 38 (2), 719–726. https://doi.org/10.1021/acs.langmuir.1c02617.