Stanford scientists have used lab-made gold nanoparticles to highlight malignant tissue in the brain, making it easier for surgeons to cut out tumors while leaving healthy bits in tact. Measuring just five millionths of an inch in diameter, these tiny glistening orbs are injected into the patient and then left to bleed out through leaky blood vessels in parts of the brain that have been damaged by the disease. They then get stuck in the bad tissue itself, marking it out for the scalpel when viewed with the right type of imaging. It's not totally new -- we've actually seen gold nanote