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This book compares tow perfusion based bioprocesses for their ability to use lower temperature and pH- values to improve volumetric productivity after an initial growth phase under standard conditions. For that CHO cells cultivated on microcarriers with a fluidised bed reactor were compared against CHO cells suspended in a continuously stirred tank reactor with an ultrasonic cell retention device. Cell culture conditions were changed to a temperature of 33 degrees Celsius and a pH-value of 6.9 in the later cultivation phase. This led to reduced media consumption and increased volumetric productivity.

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Johannes Riegler, Dipl. Ing.: Biotechnology University of Natural Resources and Applied Life Sciences, Vienna, Austria. PhD student at the Centre for Mathematics and Physics in the Life sciences and Experimental biology, University College London, UK.

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