No abstract

In ®xed bed reactors with animal cells immobilized in macroporous carriers suf®cient oxygen supply is a critical parameter. For modelling of the oxygen consumption and the oxygen pro®le in a ®xed bed oxygen gradients within the porous carriers and along the length of the ®xed bed have to be considered. For the complex geometry of the ®xed bed a model structure was assumed, that allows the calculation of the oxygen pro®le. The model for oxygen supply of the immobilized cells included the transport resistance from the bulk¯uid into the carriers and diffusion within the carriers.The model was compared with experimental data obtained with a hybridoma cell line for production of monoclonal antibodies. Model calculations and experimental data agree rather well. The mean volume-speci®c oxygen uptake rate as an indicator for the cell activity increased with the super®cial¯ow velocity of the bulk liquid¯ow, and did not depend on the length of the ®xed bed in the range tested. This indicates, that the convective transport from the bulk liquid¯ow between the carriers to the outer surface of the carriers is a dominating transport resistance besides the diffusive oxygen supply within the carriers.

No abstract