OXYGEN OPTRODE FOR CONTINUOUS PROCESSING BIOREACTORS

A Small Business Research (SBIR) project is proposed for development of an improved optical oxygen sensor for dissolved oxygen monitoring in the cell culture medium of continuous process bioreactors. The improved oxygen monitor will enable reliable long-term control of oxygen levels in continuous process reactors currently being used in drug and therapeutic protein synthesis. Further, the oxygen monitor will implement an integrated optoelectronic emitter and detector design housed within a one inch header assembly. The output will interface with any PC data acquisition card for numerical oxygen concentration readout and/or process control. The same sensor would also expand the use of many oxygen sensitive cultures not currently implemented because of the inability to accurately monitor medium having low dissolved oxygen concentrations. The specific aim of the Phase I project is the demonstration of the performance of an improved fluorescent quenching based oxygen sensing membrane chemistry in conjunction with fluorescent lifetime detection. The sensor will be evaluated for oxygen response in laboratory calibrations against solutions equilibrated gas mixtures of known composition, examined for effects of autoclaving by repeated calibrations and tested in a functional bioreactor under the low dissolved oxygen condition where current oxygen electrodes fail to provide adequate performance.