Bacterial chips
A technique to immobilise bacteria on integrated circuit (IC) chips has been developed that would provide an inexpensive way of checking pollutants in soil and water. Scientists at the US Department of Energy's Oak Ridge National Laboratory and the Centre for Environmental Biotechnology, Knoxville, USA, have initially used genetically engineered bacteria to detect naphthalene in soil. Using appropriately designed bacteria, the same principle could be applied to other pollutants. While breaking down pollutants, the bacteria emit light that is converted to an electrical signal by the chip. The chip is small and low powered and can be made to transmit signals without wires.