Wearable Vapour Sensors for Detecting Health Conditions
Uncommon Sense: Researchers Create Wearable Vapour Sensors for Detecting Health Conditions
Scientists have created a vapour sensor for monitoring health via airborne chemicals released by diabetic patients as well as those suffering from anaemia or a lung disease. Researchers at the University of Michigan have developed a new wearable vapour sensor to offer continuous disease monitoring for those suffering from diabetes , high blood pressure , lung disease or anaemia. Wearable technologies such as Google Glass and Apple iWatch are now part of an expanding market which is expected to reach $14 billion within the next 4 years. The vapour sensor can detect airborne chemicals through exhalation or release through the skin. This has been viewed by many media reports as the first wearable to channel a broad array of chemical rather than physical attributes.
"Each of these diseases has its own biomarkers that the device would be able to sense," Sherman Fan, a professor of biomedical engineering has been quoted by the media as saying. Fan has also remarked that "For diabetes, acetone is a marker, for example." Other chemicals that can be detected include nitric oxide and oxygen. Such chemicals can be markers for conditions like high BP when they are present in abnormal levels. Fan has developed the sensor with Zhaohui Zhong who is an associate professor and Girish Kulkarni, a doctoral candidate. These researchers have pointed to the value of this invention on account of it being faster, smaller and more accurate than many other wearable technologies. Apart from disease monitoring, there are other applications for the sensor as well. It can be used to detect the presence of hazardous chemical leaks or gain accurate information about air quality. Zhong has indicated that "With our platform technology, we can measure a variety of chemicals at the same time, or modify the device to target specific chemicals. There are limitless possibilities".
To create this technology, the researchers opted for an unusual approach for molecule detection. Kulkarni has explained as quoted in media reports that "Nano-electronic sensors typically depend on detecting charge transfer between the sensor and a molecule in air or solution". Previous techniques for detection of health conditions were characterised by strong bonds between detected molecules and the sensor itself and the binding leads to slow detection rates. Rather than detecting molecular charge, the technique called heterodyne mixing is to be used wherein one looks at the interaction between dipoles associated with the molecules and nano-sensor at extremely high frequencies.
This technique called graphene can result in extremely fast response times which are a tenths of a second. This is in opposition to tens or hundreds of seconds characteristic of existing technology. This can also considerably increase the sensitivity of the device. The sensor can also detect molecules in sample sizes at a ratio of many parts per billion. Nano-electronic graphene vapour sensors are completely embedded in micro-gas chromatography which is vital for vapour analysis according to the researchers. This micro-gas chromatography system can undergo integration on a single chip with low power operation. This is then embedded in a badge-sized device to be worn on the body for noninvasive and constant monitoring of certain health conditions. Fan has emphasised that this device is extremely beneficial for society.
