USE OF A SPIN-FILTER CAN REDUCE DISRUPTION OF HYBRIDOMA CELLS IN A BIOREACTOR

The possibility of damage to suspended cells arising from the introduc tion of a spin-filter rotating at high speed is examined experimentall y and theoretically. Far from increasing damage, it is shown that a sp in-filter, even when rotating at high speed, can markedly improve the survival of cells in a stirred unbuffled bioreactor. Analysis of the s hear stress generated at the filter surface shows values that are orde rs of magnitude below those shown elsewhere to be damaging to cells. T he improvement in survival seen in addition of a spin-filter to an imp eller-agitated bioreactor are explained in terms of the events associa ted with the suppression of vortices, and bubble entrainment and disen gagement.