Clean up E. coli by spilling some human proteins on it.

OK, maybe “spilling” is a little imprecise, but Scientific American has the details on how to use a blood plasma extract to clean E. coli out of drinking water:

The elegant method, devised by Teruyuki Komatsu and co-workers at Chuo University, Tokyo, begins by depositing microtubes made from alternating layers of human serum albumin (HSA) and poly-L-arginine onto a polycarbonate template. The template is then dissolved away to leave a hollow tube, which is just the right size to fit the E. coli bacterium. Key to removing E. coli from a solution is its strong binding affinity for HSA, which attracts the bacteria into the tube. So effective is this binding, that just 1.5?g of microtubes, added to a liter of contaminated water containing 100,000 bacteria were able to remove the bacteria with almost 100% efficiency. The final touch is the incorporation of a layer of magnetite (iron (II) oxide) nanoparticles into the microtubes to allow their easy removal from the solution using a magnetic field.

‘Because the microtubes are made mainly from human protein, they are safe for medical use,’ says Komatsu. ‘We are now considering how to use them in the body.’