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E-nose Opportunity for Health Monitoring

July 5, 2016

Designed at the University of Texas Dallas, the electronic nose is aimed at health monitoring through breath analysis and has the ability to perform ‘rotational spectroscopy’ at over 200GHz by using a 65nm CMOS chip.

The lead author of paper “200-280GHz CMOS transmitter for rotational spectroscopy and demonstration in gas spectroscopy and breath analysis” is Dr. Navneet Sharma. He said there have been many efforts towards building an electronic nose and that they have demonstrated that one can be built that can sense many different kinds of smells, all while remaining affordable. What the electronic nose does is detect chemical compounds in the air using rotational spectroscopy.

Rotational spectrometry analyzes the way in which electromagnetic radiation is attenuated in order to determine which chemicals and their concentrations are present in a sample. Breath contains gases from the stomach that come out of blood when exposed to air in the lungs, therefore this breath test is a blood test without taking blood samples. The University stated, “The system can detect levels of chemicals present in human breath.”

The set-up of the test involves sending energy from its dipole through a focusing lens and then down a 2m long 10 cm diameter tube that has been breathed into. The lens focusses the radiation into a receiver at the far end.
The paper presented by Sharma and his team includes diagrams as well as a detailed description of the circuit and its implementation.

After testing two of the receivers, ethanol at a concentration of 38 ppm was detected in the breath. Differing from a breathalyzer which has the tendency to confuse ethanol in the breath for acetone, the e-nose can detect gas molecules with more specificity and sensitivity. The distinction between acetone and ethanol is extremely important especially for those with Type 1 diabetes that have high concentrations of acetone in their breath.

The University said that while the e-nose could first be seen in doctors’ offices and hospitals, “As technology matures, they could become household devices. The researchers are working toward construction of a prototype programmable electronic nose that can be made available for beta testing sometime in early 2018.”