The wood revolution in materials science
After many years spent trying to assemble nanomaterials atom-by-atom, usually from carbon or silicon, scientists are returning to something simpler and greener.
Wood. (Picture by Andrew Hancock of Purdue University.)
Wood and wood products, like paper, have a natural biological structure. They grew from the ground. With a little chemical manipulation, this makes them a great scaffold for some important uses.
At Purdue paper acts as a scaffold for a magnetic ink that can let us print micro-motors at a fraction of the cost of building them from silicon.
The Boilermakers call it "Ferropaper," because the coating consists of mineral oil and iron oxide. Babak Ziaie (above) notes that paper is a "porous matrix" that can hold a lot of oil and iron.
The result could go into tiny fingers on the end of a surgical robot, making surgery less invasive, or into tweezers small enough to manipulate individual cells.
More important, it's dirt cheap.
Ziaie calls it 100 times cheaper than assembling a mico-machine from silicon. Coat the result in a biochemical plastic film and it's water resistant. Ziaie's paper will be presented in Hong Kong later this month -- he wrote it with two Chinese graduate students. (Call it a homecoming with dim sum.)
Meanwhile, Italian researchers have used the porous qualities of wood to produce an artificial bone that is so lifelike real bone fuses naturally to it.
They start with rattan wood, the same stuff used in a lovely Amish chair I have in my living room. The wood is heated under pressure, then calcium and phosphates are added, resulting in a white substance that can be formed into any shape needed.
As the BBC notes, the material looks just like bone under a microscope, and it never has to be replaced. For those whose faces have been ravaged by disease, or whose knees are being damaged by arthritis, or who have suffered cancer that killed their natural bones, this is going to be huge.
In both these cases it's the natural structure of wood and paper -- a structure similar to that found in our own bodies -- that is key.
You really can't beat nature.
This post was originally published on Smartplanet.com