Noninvasive, Real-Time Monitoring of Oxygen and pH During E. coli Fermentation Using Optical Sensors

monitoring biological parameters in bioreactor environments, we placed oxygenand pH-sensitive adhesive patches inside a bioflask to monitor conditions during an E. coli fermentation reaction. Bioreactors are closed-environment systems where the cells are cultured under specific conditions to synthesize the final product. Such systems require constant monitoring of DO and pH to optimize the bioprocesses. Optical sensors were used to provide oxygen and pH measurements in the liquid phase of the bioreactor. Advances in sensor materials and optoelectronics have enabled novel optical sensors for applications in life sciences, pharmaceuticals, biotechnology and more. Compared with electrochemical sensing techniques such as galvanic sensors, optical sensors can be made in small and customizable form factors, allow non-intrusive measurements and do not consume the sample.