An analysis performed by a group of researchers at the University of Maine and the Northwestern University paves the way to understand the challenges that need to be tackled in order to realize the full potential of artificial molecular machines.
The University of Maine’s Dean Astumian stated that all nanoscale machines are experiencing persistent collision with the surrounding molecules, causing thermal noise. Effort to reduce thermal noise effects to obtain accurately controlled machines by imitating macroscopic approaches was a failure, Astumian pointed out.
At present, researchers are working on a chemical method wherein thermal noise is used for constructive purposes. Astumian commented that exploiting energy at the nanoscale individual molecules is to create a forward motion rather than an unnecessary backward motion.
Synthetic molecular machine has to function at all scales in order to meet its great promise. The Northwestern University’s Sir Fraser Stoddart stated that to make single molecular switches to perform useful works at macroscale, they need to be arranged temporally and spatially. He suggested that metal-organic architectures are capable of meeting this challenge due their strong and highly integrated frameworks.
Synthetic molecular machines performed useful works at an energy-conversion efficiency of over 75%, which is comparatively higher than the typical car engine’s energy-conversion efficiency of 20-30% or even better than the highly efficient diesel engines having an energy-conversion efficacy of 50%.
The Northwestern University’s Bartosz A. Grzybowski stated that synthetic molecular machine converts chemical energy directly into mechanical work and eliminates the unnecessary heat conversion process, resulting in its high energy-conversion efficacy. Based on the promising applications of synthetic molecular machines, the first person who designs a nanoscale robotic arm that can accurately control position nanoscale matter can win Feynman's Grand Prize, Grzybowski added.