Scientists at the John Innes Centre have successfully added iron-containing molecules to the surface of this virus. The result is electronically active nanoparticles. They believe this will in the future facilitate the manufacture of nanotechnology electrical devices.

The work is yet another example of how scientists are now trying to engineer objects on the scale of atoms and molecules.

According to Dr. David Evans, a chemist at the Centre, mosaic viruses are ideal for this purpose because they have a defined size and a spherical shape.

This is a big advantage for microscopic engineers. Ordinarily, making such tiny particles of identical size is quite challenging.

The Evans team was able to attach molecules called ferrocenes to amino acids receptors already built in to the virus’ surfaces. They have been able to attach 240 such particles, creating what is effectively a molecular capacitor.

Capacitors store an electrical charge then release it in a pulse. They are used in a wide variety of electronic circuits, tools and appliances. One application the researchers envision that I find particularly exciting is use in biosensors.

Biosensors are essentially devices that monitor biological processes. When a process gets out of bounds (too high or too low), the sensor emits a signal that indicates a need for attention.

By enabling the manufacture of tiny electrical circuits, the sensor apparatus could be powered by a microbattery — such as that being developed by Transformational Technologies Portfolio holding Nuclear Solutions Inc. (NSOL: OTC BB) — and signal the outside world.

Most current biosensors work on a very large scale, compared to a virus. There are numerous advantages of being able to make them so small. Among these are:

• Ability to attach the biosensor inconspicuously in a place it ordinarily might not fit. For example, such sensors might be able to enter the brain through the capillary system and monitor brain chemistry without need for surgery and no disruption to brain function. They could offer an early warning of dementia.
• Test birds could be used as the proverbial “canary in a mineshaft” and be sent into flocks that might harbor bird flu. The sensors would be programmed to detect the flu before overt symptoms would appear, enabling prophylactic action.
• Such sensors could potentially be deployed throughout a person’s body, resting there and monitoring to detect unique chemicals made by cancer cells. Earlier detection of cancer would enable a wider variety of less painful and cheaper treatment options.
• Military uses would include early detection of chemical biological warfare agents (CBW). Microsensors could potentially be deployed in a stealth manner.

A variety of companies working in the biosensor field are looking for ways to miniaturize these devices. Some nanotechnology research firms are developing ways to do this artificially.

Whenever I see a program that takes what nature has already developed in the nano-world and finds a way to modify it for human purposes, I get excited. The reason is that, in most cases, nature has already found a very efficient way to do what is needed.

For example, have you noticed that doctors’ needles have become less painful in recent years? This is because researchers studying snake fangs discovered a unique pattern that minimizes tearing when penetration happens. That pattern was borrowed for needles.

In the race to build successful nanotechnology devices, those who piggyback off “nature’s nanotechnology” have a leg up. I’ll continue to be watching for such research breakthroughs, and the small companies that get licensed to commercialize them.

To your profitable future,
Jonathan Kolber
April 18, 2007

Investing in Nanotechnology was originally featured in the Penny Sleuth.