In this work, we have demonstrated a universal optical platform capable of monitoring pH or DO sensors. It uses the principle of ratio-metric fluorescence measurements for pH and fluorescence lifetime measurements for DO. The platform is capable of seamlessly switching between these two modes. It is also capable of auto recognition of the sensor type. The platform can operate both with patch-type or fiber optic type of sensors. The platform has measurement accuracy of about 0.08 pH units and approximately 5 % air saturation with oxygen. Additionally, an approach to obtain identical calibrations between several devices is presented.
The described platform has been tested in actual bioprocesses and has been found adequate for continuous bioprocess monitoring.