FAQs

The neck geometry of the flask plays a bigger role in cultivations than the plug. Generally wide necks are beneficial for gas exchange. Under normal conditions the mass transfer resistance of sterile closures is far smaller than the resistance of the gas-liquid interface. A new method to determine the mass transfer resistance of different sterile closures by measuring the water evaporation rate was published in:
Mass transfer resistance of sterile plugs in shaking bioreactors
Mrotzek C, Anderlei T, Henzler H, Buechs J
Biochem Eng J. (2001);Vol. 7, No. 2, pp 107-112