ON THE SETTLING AND RESPONSE TIMES OF UNDERDAMPED SECOND-ORDER SYSTEMS

Chinese hamster ovary (CHO) cells is one of the most widely used production host for the commercial production of biopharmaceuticals product. They have been extensively studied and developed, and today provide a stable platform for producing monoclonal antibodies and recombinant proteins. This study focused on the production of recombinant protein in suspension culture of CHO cells in spinner flask and shake flask.The CHO cells were transfected with DNA plasmid containing lac Z gene which codes for β-galactosidase. The β-galactosidase-expressing CHO cells were adapted to suspension culture. The agitation speed for both spinner and shake flask were adjusted accordingly. The experiments were carried out in duplicate and samples were taken for cell count, determination of glucose consumption, lactate production and protein level by using biochemical assay. Results showed that cell growth in spinner flask is more favorable than in shake flask. The cell concentration in spinner flask is 58% higher than in shake flask. On the other hand, specific activity of β-galactosidase is 25% higher in spinner flask compared to shake flask, at the same agitation speed.