Date of Award
Master of Applied Science (MASc)
Electrical and Computer Engineering
Thomas E. Doyle
An electro-optical sensor module was designed to monitor the level of dissolved oxygen (DO) using the method of frequency domain ﬂuoroscopy. Frequency domain ﬂuoroscopy is an optical method that detects the concentration of an analyte by indirectly monitoring the ﬂuorescent lifetime decay. A planar ﬁlm containing oxygen sensitive ﬂuorophores interacts with a liquid solution, where the percent DO dictates the ﬂuorescent lifetime decay. Amplitude modulated LED emission is created using an electrically implemented oscillator, exciting the oxygen sensitive ﬂuorophores. The emission light from the ﬂuorophores is detected by a photodiode and conditioned. The timing characteristics of the excitation and emission light waveforms are interpreted by a microcontroller. Time delay values have been correlated to actual percent DO values experimentally, and appropriate data modeling has been implemented for calibration purposes. This design is appropriate for application in bioreactors, presenting a functional and cost effective design. Future research can be performed to extrapolate the microcontroller platform to host a pH module, cell number module and glucose module, providing sufﬁcient feedback to an automated bioreactor systems.
Rosa, Raelyn K., "Design of a Dissolved Oxygen Optical Sensing Device for Cell Growth and Metabolism Monitoring in Bioreactors" (2012). Open Access Dissertations and Theses. Paper 6778.
McMaster University Library
Biological Engineering Commons, Biomedical Commons, Biomedical devices and instrumentation Commons, Biotechnology Commons, Electrical and Electronics Commons, Electromagnetics and photonics Commons, Molecular, cellular, and tissue engineering Commons, Systems and integrative engineering Commons