Development of Multi-function Respiratory Device pplied on Asthma Assessment

Asthma is a global chronic disease prevalent among the age group of 20 to 44 years. People affected by asthma account for 5% of adult population and reach even over 10% of all children. The nitric oxide (NO) exhaled from nose or mouth is highly correlated to asthma, so NO is regarded as an indicator of asthma. Besides, the patient’s lung volume and expiration flow are inferior to the normal. This research focused on the development of multi-functional respiratory device which can be used for asthma assessment; the device is a prototype system made of the hot wire chip with microcontroller. The current function includes switching user, expiration test and real time data display on the LCD, and Bluetooth transmission of the data to remote PC using user specific code. The key parameters monitored by this system are lung volume and respiration flow. In addition, we also attempt to develop a surface plasmon resonance (SPR) sensor to detect NO. Combined with the SPR gas sensor, the respiratory device is capable of simultaneously measuring more than two indicators of asthma.here are two types of design for SPR gas sensor. The first one is Au-WO3 composite nanofilm; the optimal SPR resonance is found by adjusting the volume fraction of Au-WO3 using a simulation software and the design is then fabricated using Pulsed Laser Deposition (PLD) technology; the second one is conductive polymer PEDOT deposited by cyclic voltammetry unto the Au film. The PEDOT thickness can be controlled by varying the fabrication condition. The exhaled NO concentration over 16ppb is regarded as the diagnostic criterion in asthma assessment; therefore, a miniature device using the conductive polymer and the innovative composite nanofilm to achieve low concentration level sensing is a goal in the future development of asthma detection device.