London: Researchers from the University of Leuven (KU Leuven) in Belgium have built a very sensitive electronic nose with metal-organic frameworks (MOFs) that can detect pesticides and nerve gas in very low concentrations. "MOFs are like microscopic sponges. They can absorb quite a lot of gas into their minuscule pores,” said post-doctoral researcher Ivo Stassen. The chemical sensor can easily be integrated into existing electronic devices. “You can apply the MOF as a thin film over the surface of, for instance, an electric circuit. Therefore, it's fairly easy to equip a smartphone with a gas sensor for pesticides and nerve gas,” added professor Rob Ameloot. The best known electronic nose is the breathalyser. As drivers breathe into the device, a chemical sensor measures the amount of alcohol in their breath. This chemical reaction is then converted into an electronic signal, allowing the police officer to read off the result. "We created a MOF that absorbs the phosphonates found in pesticides and nerve gases. This means you can use it to find traces of chemical weapons such as sarin or to identify the residue of pesticides on food,” added Stassen. This MOF is the most sensitive gas sensor to date for these dangerous substances. “Further research will allow us to examine other applications as well," Professor Ameloot noted in a university statement. “MOFs can measure very low concentrations, so we could use them to screen someone's breath for diseases such as lung cancer and multiple sclerosis (MS) in an early stage,” he added.