Development of Ultra-Small 3-Electrode Sensors and Driver IC for Expiratory Analysis
Development of Multi-Channel Electrode Sensors for Medical Applications
The exhalation of air that comes out when a person breathes out includes various organic compound gases from the body. Some of these gases vary in concentration depending on the health condition of the person. For example, toluene, which is a marker for lung cancer, is detected at only about 20ppb in the exhalation of healthy persons, but at more than 100ppb in the case of lung cancer patients. Acetone, a diabetic marker, is found at 0.80ppm in the exhalation of healthy persons but 1.71ppm or more in the exhalation of diabetic patients. Accurately analyzing the concentration of specific gases will make it possible to diagnose a disease cheaply and easily without the need for blood test or magnetic resonance imaging (MRI). In fact, disease-detecting biosensor technologies based on this principle are already being developed, and related research is being actively carried out around the world. However, these technologies still have some limitations in selectively detecting target gases, because of their very low content level and interference from various other gases contained in the breath.
The research team led by professor Park Chong-Ook has long worked on developing an expiration analysis sensor with high sensitivity and selectivity in order to overcome these challenges The research team has developed a high-sensitivity sensing material with a special combination that increases the response sensitivity to gas, thereby raising the threshold for detection. In addition, by newly designing a new 3-electrode sensor to replace the existing 4-electrode sensor, the research team successfully minimized the size of the unit sensor as well as its power consumption. To solve the problem of selectivity, which is a persistent problem of this type of sensor, four 3-electrode sensors were connected to an array sensor, and pattern recognition technology was applied. Further, in order to deal with various driver-related problems caused by the special characteristics of a three-electrode sensor, the research team designed new driving circuit units.
The newly adopted 3-electrode structure in this study is particularly significant, since it moves away from the existing frame of 4-electrode sensor technology which is used in advanced countries such as Japan and Germany, thereby establishing a foundation for competing with advanced countries based on the new framework. The 3-electrode sensors, which are characterized by their miniaturization and low power consumption, can also be applied to various devices requiring miniaturization and portability. Indeed, by overcoming many of the limitations of the existing technology, whose use was limited for industrial purposes, this technology is anticipated to emerge as one of the key devices for advanced next generation systems, in applications in such diverse fields as medical treatment, household appliances, IOT, etc.
Prof. Park, Chong-Ook
2016 Annual Report