Synthetic Molecular Walkers

  • David A. Leigh
  • Urszula Lewandowska
  • Bartosz Lewandowski
  • Miriam R. Wilson
Part of the Topics in Current Chemistry book series (TOPCURRCHEM, volume 354)


In biological systems, molecular motors have been developed to harness Brownian motion and perform specific tasks. Among the cytoskeletal motor proteins, kinesins ensure directional transport of cargoes to the periphery of the cell by taking discrete steps along microtubular tracks. In the past decade there has been an increasing interest in the development of molecules that mimic aspects of the dynamics of biological systems and can became a starting point for the creation of artificial transport systems.

To date, both DNA-based and small-molecule walkers have been developed, each taking advantage of the different chemistries available to them. DNA strollers exploit orthogonal base pairing and utilize strand-displacement reactions to control the relative association of the component parts. Small-molecule walkers take advantage of the reversibility of weak noncovalent interactions as well as the robustness of dynamic covalent bonds in order to transport molecular fragments along surfaces and molecular tracks using both diffusional processes and ratchet mechanisms. Here we review both types of synthetic systems, including their designs, dynamics, and how they are being used to perform functions by controlled mechanical motion at the molecular level.


Diffusion processes DNA machines DNA motors DNA walkers Dynamic covalent chemistry Michael addition Molecular machines Molecular motors Molecular walkers One-dimensional random walk 



Atomic force microscopy






Base pair(s)




Dynamic covalent chemistry; also dynamic combinatorial chemistry




Deoxyribonucleic acid


Deoxyribonucleic acids




(Entgegen); opposite


Electrospray ionisation


Equilibrium transfer alkylating cross-linking reagent(s)




Holliday junction


High speed






Millielectron volt(s)




Mass spectrometry




Nuclear magnetic resonance






Ribonucleic acid




Scanning tunnelling microscopy


(Zusammen); together


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Copyright information

© Springer-Verlag Berlin Heidelberg 2014

Authors and Affiliations

  • David A. Leigh
    • 1
  • Urszula Lewandowska
    • 1
  • Bartosz Lewandowski
    • 1
  • Miriam R. Wilson
    • 1
  1. 1.School of ChemistryUniversity of ManchesterManchesterUK

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