JUN 06, 2017 6:34 PM PDT

Big Buzz from Tiny Motors

Molecular motors are molecule-sized machines that are capable of transforming an energy source (chemical, light, heat, etc) into kinetic motion, and the human body has millions of them. Take the ATP synthase for example, it works like a miniature rotary motor. Powered by the proton gradient across the inner mitochondrial membrane, these protein-based biological motors turn ADP into ATP - the energy currency.

The idea of a synthetic motor was first proposed by the nanotechnology pioneer Richard Feynman. This concept was largely intriguing because it can provide kinetic energy and mobility to miniature human-made machines. A prototype model driven by chemical reactions was first developed by a research team led by T. Ross Kelly from Boston College. Their design consists of a three-bladed triptycene rotor and a helicene. The motor is capable of rotating 120 degree and each rotation involves 5 chemical reactions. Dutch chemist Ben L. Feringa and his group tried a different approach. They created a light-driven motor that is made of a bis-helicene molecule with an alkene axial.  The motor finishes a 360-degree rotation with a 4-step photoisomerization-dictated process. The principle of Feringa’s design was later incorporated into the development of an early generation nanocar.  For his exceptional contribution to molecular motor, Ben L. Feringa received the Nobel Prize in Chemistry in 2016.

Structure of Nanocar with C60 fullerene wheels. Credit: wikipedia/James Tour Research group

Related reading : nanocar and nanocar race

Synthetic molecular motor-rotor machine driven by light. A, motor axial. B, rotor axial. Credit: the Feringa Research group

Recently the team led by the Nobel laureate created a more sophisticated motor design - a molecular motor coupled to a rotor. This motor-rotor combo has three main body components: a fluorenyl group (the stationary base), an indany group (the motor), and a naphthyl group (the rotor). How does this new complex yet small machine work? Try picturing a horizontally rotary ride in the amusement park: it has a main motor axial through which the primary rotation happens, and a rotor axial that allows secondary rotation. What is marvelous about this design is that the motor and rotor are perfectly synchronized – they always face each other at the same side during movement. When both parts finish one round of rotation, and they generate motion to propel the body forward on a single direction.

To explain the idea behind this design, Ben Feringa said: “This is fundamental research about how to control motion at the molecular level and how then to use it to synchronize motion and amplify motion.” The synchronized rotation can only be achieved by coupling motion and preventing free rotation of the rotor, as he pointed out. For the future, Feringa’s group is expecting to create machinery that can amplify the molecular machines’ motion to larger movements or transmit motion over longer distances.

Source: Chemical & Engineering News

About the Author
  • Graduated with a bachelor degree in Pharmaceutical Science and a master degree in neuropharmacology, Daniel is a radiopharmaceutical and radiobiology expert based in Ottawa, Canada. With years of experience in biomedical R&D, Daniel is very into writing. He is constantly fascinated by what's happening in the world of science. He hopes to capture the public's interest and promote scientific literacy with his trending news articles. The recurring topics in his Chemistry & Physics trending news section include alternative energy, material science, theoretical physics, medical imaging, and green chemistry.
You May Also Like
OCT 18, 2019
Chemistry & Physics
OCT 18, 2019
Scientists Gained Insights into Nuclear Fusion from Mayonnaise
Nuclear fusion is considered as the energy of the future. Researchers across the globe have been striving to build fusion reactors that can eventually be u...
NOV 06, 2019
Chemistry & Physics
NOV 06, 2019
Radioactive Spill? Self-propelled Microbots to the Rescue
Scientists have been looking for an effective method to clean up radioactive elements in industrial wastewater and accidental spill, to support and boost t...
NOV 18, 2019
Chemistry & Physics
NOV 18, 2019
The Elements that Could Go "Extinct"?
Extinction doesn't just happen in the world of biology — it might also have to chemical elements. Our world of modern technologies relies on a lo...
NOV 21, 2019
Chemistry & Physics
NOV 21, 2019
Pharmacist Who Debunked False Vit C Claim Honored by the Maddox Prize
"Sense about Science" is a UK-based NGO that promotes the public understanding of science. Every year the organization gives the John Maddox Priz...
DEC 01, 2019
Space & Astronomy
DEC 01, 2019
Jupiter's Great Red Spot May Not Be Dying After All
Most people recognize Jupiter as the largest known planet in our solar system, but there’s another eccentric quality about the planet that helps it s...
DEC 31, 2019
Space & Astronomy
DEC 31, 2019
Why Does This Star Dim Unpredictably?
KIC 8462852, also known as Tabby’s Star or the infamous ‘alien megastructure star,’ is peculiar because the star’s light seems to d...
Loading Comments...