Nanomotor

A nanomotor is a molecular or nanoscale device capable of converting energy into movement. It can typically generate forces on the order of piconewtons.[1][2][3][4]

A proposed branch of research is the integration of molecular motor proteins found in living cells into molecular motors implanted in artificial devices. Such a motor protein would be able to move a "cargo" within that device, via protein dynamics, similarly to how kinesin moves various molecules along tracks of microtubules inside cells.

Starting and stopping the movement of such motor proteins would involve caging the ATP in molecular structures sensitive to UV light. Pulses of UV illumination would thus provide pulses of movement. DNA nanomachines, based on changes between two molecular conformations of DNA in response to various external triggers, have also been described.

Chemically powered or externally powered artificial nanomotors have also been prepared using synthetic materials and chemical methods.

Nanotube and nanowire motors

Catalytic nanowire motors that exhibit autonomous self propulsion in the presence of a hydrogen peroxide fuel were first developed by Tom Mallouk and Ayusman Sen at Penn State University.[5] The nanomotors have autonomous, non-Brownian motion that stems from propulsion via catalytic generation of chemical gradients. Some other early work on catalytic nanomotors was investigated by researchers at the University of Toronto,[6] and in Dresden Germany, where bubble-powered catalytic microtube microengines were first developed.[7] Bubble-induced propulsion enables motor movement in relevant biological fluids, but typically requires toxic fuels such as hydrogen peroxide, so it is so far limited to in vitro applications. These catalytic motors are autonomous in that they do not require external magnetic, electric, or optical fields as energy sources. They also exhibit collective behavior such as schooling, chemotaxis, and predator-prey interactions that are mimetic of biological microorganisms.[8] Researchers led by Joseph Wang have made a breakthrough development in 2008 by making a new generation of fuel-driven catalytic nanomotors that are up to 10 times more powerful than existing nanomachines.[9] It is a major step forward to a practical energy source for powering tomorrow's nanomachines.[10] The large force of recently developed nanomotors holds major promise for important cargo-towing applications ranging from cell sorting in microchip devices to directed drug delivery.

See also

References

  1. ↑ Dreyfus, R.; Baudry, J.; Roper, M. L.; Fermigier, M.; Stone, H. A.; Bibette, J., Microscopic artificial swimmers. Nature 2005, 437, 862-5.
  2. ↑ S. Bamrungsap, J. A. Phillips, X. Xiong, Y. Kim, H. Wang, H. Liu, A. Hebard, and W. Tan, "Magnetically driven single DNA nanomotor," Small, vol. 7, no. 5, p. 60 2011.
  3. ↑ T. E. Mallouk and A. Sen, "Powering nanorobots," Scientific American, May 2009, pp. 72-77
  4. ↑ J. Wang, "Nanomachines: Fundamental and Application", Wiley, 2013
  5. ↑ W. F. Paxton, K. C. Kistler, C. C. Olmeda, A. Sen, S. K. St. Angelo, Y. Cao, T. E. Mallouk, P. Lammert, and V. H. Crespi, "Autonomous Movement of Striped Nanorods," J. Am. Chem. Soc., 126, 13424-13431 (2004)
  6. ↑ S. Fournier-Bidoz, A. C. Arsenault, I. Manners, and G. A. Ozin, "Synthetic Self-Propelled Nanorotors," Chem. Comm. 2005, 441-443
  7. ↑ Mei, Y.; Solovev, A. A.; Sanchez, S.; Schmidt, O. G., "Rolled-up nanotech on polymers: from basic perception to self-propelled catalytic microengines," Chem Soc Rev 2011, 40, 2109-19.
  8. ↑ “Schooling Behavior of Light-Powered Autonomous Micromotors in Water” Michael Ibele, Thomas E. Mallouk and Ayusman Sen, Angew. Chem. Int. Ed. 2009, 48, 3308-3312.
  9. ↑ Speeding up catalytic nanomotors with carbon nanotubes
  10. ↑ J. Wang, "Nano-machines", Wiley, 2012

External links