Prof. Ozin writes about his nanomachine dream on CIFAR website.
Dear Friend of CIFAR,
My dream of building useful nanomachines might sound futuristic, maybe even far-fetched. But Nature has created and relied on nanomachines for millions of years. Take a bacterium like E. coli, for example, which moves around through a whip-like motion of its flagella – its nanobiological motor. There’s also the ribosome – a nano-sized machine that all cells depend on – which assembles the workhorses of cell function, proteins.
Inspired by Nature, I am making a Nanomachine Dream come to life in the lab. Using synthetic building blocks, I am creating a whole new class of nano-sized motors that might someday transport medicine in the human body, move cargo around computer chips, and search and destroy toxins in polluted water streams.
My research team has developed a nanomotor out of a tiny rod composed of two metal segments, nickel and gold. The nickel segment functions as a catalyst for decomposing hydrogen peroxide (H2O2) in an aqueous environment. During the decomposition, oxygen is produced at the surface of the nickel segment, according to the simple chemical reaction:
2H2O2 (liquid) -> O2 (gas) + 2H2O (liquid)
The oxygen forms as nanoscale bubbles that evolve off the nickel. These bubbles act as a driving force to propel the nanorod forward. We chose gold for the other segment, but any material that is stable in a liquid solution and does not react with hydrogen peroxide works.
Our nanorods do more than move – they actually rotate in two different ways. One rotation resembles the arm of a clock, while the other can be described as a circular orbit. These movements, and their associated speed, depend on the concentration of hydrogen peroxide around the nanorod, as well as the dimensions of its nickel segment.
I first started studying nanorods with applications like information storage and processing in mind. The finding that these rods exhibit locomotion was exciting and completely serendipitous. My hope is that by studying different synthetic nanomachine systems, we will gain a better understanding of how Nature’s nanomachines, such as the E. coli’s flagellum and the cell’s ribosome, manage to move.
It’s a cycle of discovery – the more we learn about how Nature’s nanomachines work, the greater knowledge we gain for creating powerful artificial analogues that could solve some of the great challenges facing medicine, computing and the environment.
Best wishes from the frontiers of human knowledge.
Geoff Ozin
Fellow, Nanoelectronics program
Canadian Institute for Advanced Research