Researchers have created two tiny instruments capable of detecting a range of contaminants, from molecules to whole bacteria, in food and water. The device can be arranged to search for specific things, for example, if the organism to be detected is E. coli, the cantilever could be coated in antibodies specific to E. coli cells. Many different molecules or organisms can also be recognized simultaneously. The applications for this new technology are abundant. The sensors can detect DNA and hence may be used to test for human genetic diseases. They are also extremely sensitive and can measure deflections of just one nanometre, so are able to detect the presence of very small molecules. A whole bacteria and even parts of bacteria can be identified, making the sensors ideal for testing the quality of water and food samples. A lid device with tiny instruments could be included in food packaging. When a food is infected, the control unit in the plastic wrapping becomes coloured and thus the simple colour indicator can show the quality of the food. It requires no external energy and is cheap to make.