Imitation spleen proteins hold key to fresh water

The human spleen doesn't receive much good press, but the Electronic Power Research Institute has come up with a spleen-inspired molecule that could expand the world's water supply.

EPRI's MagMolecules are designer molecules that can extract specific contaminants from water. The Californian firm is testing one molecule that can remove radioactive materials, such as cesium, from the water that circulates inside nuclear power plants, said Clark Gellings, vice president of innovation at EPRI.

Radioactive materials corrode surfaces and equipment in the plants, so removing them extends the life of the facility, Gellings said at the Foresight Nanotechnology Conference here.

"But there's no reason MagMolecules couldn't be used in other applications," he added, such as removing contaminants from groundwater.

Investors are putting more money into so-called clean technologies, which replace existing processes or products with ones that pollute less. Most of the interest has centred around alternative energy ideas, but the concept is spreading.

Some have predicted that, as with oil, the world will face drinking-water shortages in the coming decades. Dean Kamen, inventor of the Segway scooter, has come up with a system, based on a Stirling engine, that can create potable water. At University of California at Berkeley, professors and students are testing a system that cleans water with UV light.

Magmolecules are synthetic versions of ferritins, proteins produced in the spleen and liver. Naturally produced ferritins attract and hold iron.

The hard-drive industry has used synthetic magnoferritins in its products for years. British start-up NanoMagnetics is experimenting with ways to make ferritin-based memory. (While it plans to use synthetic molecules one day, NanoMagnetics gets ferritins from cows for its prototypes.)

EPRI's research has revolved around tweaking magnoferritins so they attract different types of materials. Soon the group will commercialise its first MagMolecules, Gellings said.

The MagMolecule technology also could greatly reduce the amount of radioactive waste from nuclear plants, according to EPRO. At present, evaporation is used to extract solid waste from water used at the plant. Though the solids can have radioactive material inside, the amount that can be extracted through evaporation is often miniscule.