Professor Hancock began working on the breathalyser technology in the hope of developing a way of screening patients for diabetes, a disease which creates elevated levels of acetone in breath.
It works by using a detection method known as spectroscopy which measures the wavelengths of light that are absorbed by different molecules in a gas.
By shining an infrared laser through a complex series of mirrors they can detect even tiny changes in the levels of acetone when a person breathes into the breathalyser.
Professor Hancock said: “We started thinking that our techniques could be applied to the detection of different chemicals in human breath and would that be useful if there was a correlation between the gases in human breath and disease.
“When you are ill, the concentrations of different molecules change.
“Acetone is associated with diabetes and we have already developed a detection system that can see acetone at about the levels that are important for the diagnosis of diabetes.
“We would like to set this up as a screening method for diabetes as there are so many people who suffer from it, particularly type 2 diabetes, but they don’t know they have it.”
At present diabetes is diagnosed using a blood test that has to be sent to a laboratory for analysis but a breath test would allow patients to be diagnosed in their doctors surgeries without having to give blood.
Professor Hancock is also about to start a clinical trial to examine whether acetone can be used to monitor the level of sugar, or glucose, in the blood.
Diabetes sufferers have to take regular blood samples by pricking their fingers during the day to ensure their blood glucose levels do not become too high.
Professor Hancock added: “It is pretty distressing for people who have to prick their finger four times a day to test their blood glucose levels, particularly for children.
“We hope to eventually produce a hand-held instrument that can be breathed into by diabetes sufferers.”