However, one thing that still needs to get smaller, if computers are going to be able to deal with ever increasingly sophisticated devices that eat up memory, is the hard drive.
Bio tech of the future
The more bits that can be crammed onto the hard disk the better. With this in mind, a new paper in the scientific journal Small has got nano enthusiasts all giddy with excitement – apparently harnessing bacteria is the key to making hard drives smaller!
We’re using and abusing nature because it’s had billions of years to do all of its experiments through evolution
A bacterium known as Magnetospirillum Magneitcum, which is usually found in oxygen-scarce shallow water, has a peculiar function in that it navigates using the earth’s magnetic field. When the bacteria ingests iron, proteins in its body react with the metal to create nano-sized crystals of the most magnetic, naturally occurring substance on earth, Magnetite.
Using bacteria to make hard drives
A group of scientists from Leeds, led by Sarah Staniland, have been extracting the protein, Mms6, from the bacteria in order to harness its capability for turning iron into magnetite. This in turn is being tested as an alternative to argon ions used in traditional hard drives and it is hoped with this efficient mineral the hard drives of the future will be able to hold a much larger amount of information in a much smaller amount of space compared to today’s hard drives.
Staniland says, “We’re using and abusing nature because it’s had billions of years to do all of its experiments through evolution, so there is almost no point in us starting from scratch.”
In traditional hard drives, computer memory is stored in the form of ‘bits’ which are created by the polarization of the granular magnetic material on the surface. These granules have become so small that if they get any smaller data becomes unstable.
In order to overcome this, Staniland’s team are replacing granular media with bit-patterned media – small, patterned magnetic dots which each store a bit of data.
We are quickly reaching the limits of traditional electronic manufacturing as computer components get smaller
The team took a gold surface covered in chemicals in a chessboard pattern. One type of square binds proteins and the other repels them. They applied the protein to the surface and then coated it in an iron solution – the squares that bind the proteins then turn the iron into Magnetite while the squares that repel the protein don’t.
Turning to nature
Staniland says, “We are quickly reaching the limits of traditional electronic manufacturing as computer components get smaller…Nature has provided us with the Perfect tool to (deal) with this problem.”
However, the smallest square they have made in recent experiments is 20 micrometers wide which would make the hard drive far larger than standard ones.
The idea though, is to create a single iron particle per square with the potential to store as much as 1 terabyte of data per square inch –this would open up a whole new world of storage space that would take up very little physical space.



