Question

Baffles are not needed in Up and down agitation bioreactor.

(a) True

(b) False

I had been asked this question during an interview.

My doubt is from Bioreactor Configurations in division Reactor Engineering of Bioprocess Engineering

Answer 1

The correct answer is (a) True

The explanation is: Up and down agitators are useful to avoid shear stress to the cells. These are done by instead of a traditional propeller agitator, which requires an expensive motor and magnetic coupling. Vertical up and down motion is achieved by a motor together with an inexpensive membrane perfectly assure sterility and produce an efficient mixing without formation of a vortex (no baffles needed). At the same time this type of mixing is gentler on cells and produces less foam.