Can you tell me what are the advantages of using a protectant over managing mixing speed, impeller choice etc. to control shear?

Answer

Poloxamer 188 is commonly used in the biopharmaceutical industry as a cell culture media additive to protect cells from the turbulent environment of sparged bioreactors. It has been demonstrated that Poloxamer 188 can function as highly effective shear protectant as it decreases physical damage to suspensions of animal cell cultures by physical and biochemical means. Managing mixing time and speed, impeller choice, agitation, gas entrance velocities etc. in typical culture conditions can support sparging-associated cell damage. Nevertheless achievable cell densities and thereby process productivity are limited without a shear protectant especially with regard to the industry trend towards higher cell densities e.g. perfusion processes. From our view there is currently no real alternative to the addition of a shear protectant.