Optical �Dog Nose� Developed to Detect Cancer, Other Diseases Researchers at the University of Adelaide in Australia are using optical spectroscopy to develop a quick, non-invasive �breath test� they believe will have the potential to screen for a variety of diseases, including diabetes, infections and cancers.The research team, led by Dr. James Anstie, Australian Research Council (ARC) Research Fellow with the University Institute for Photonics and Advanced Sensing (IPAS), compared the instrument to an �optical dog nose� which uses a special laser to measure the molecular content of a sample of gas.�Our device will use broad-band cavity-enhanced frequency-comb spectroscopy to achieve sensitivities to molecular concentrations in the low parts-per-million, high parts-per-billion levels � which is where you need to be to start reliably detecting the molecular content of breath,� Anstie told Bioscience Technology.�Rather than sniffing out a variety of smells as a dog would, the laser system uses light to �sense� the range of molecules that are present in the sample,� Anstie said in a university press release.�Those molecules are by-products of metabolic processes in the body and their levels change when things go wrong.  There have been good studies undertaken around the world which show that diseases like lung and oesophageal cancer, asthma and diabetes can be detected in this way, even before external symptoms are showing.�However, Anstie told Bioscience Technology, �Other conditions, although they have a clear molecular signature in the breath may be masked by the general complexity involved in getting a good repeatable sample.�  That means Anstie team will need to work with medical researchers to improve sampling techniques, and improve the analysis of data coming out of the device, he said.Although there is much research needed in breath analysis, the team believes a working prototype could be ready in two to three years, with a commercial product available within five years. Antsie said the team must show they can accurately determine molecular concentrations in simulated breath samples, before extending into actual breath samples in about a year.Up next the team plans to extend the optical range of the device and thus the number of molecules they can look at.  �We also need to improve the sensitivity of the device by sampling inside a Fabry Perot cavity.�   The research, published in the journal Optics Express, was funded through the ARC, the Priemeir Research and Industry Fund and a South Australian Government Catalyst Research Grant.