Noninvasive Optical Sensor Technology in Shake Flasks For Mammalian Cell Cultures

Wen-Lin Tsai, Jennifer L. Autsen, Julie Ma, Terry Hudson, and Jun Luo

BPI Vol. 10 No. 1, 2012

In process development, appropriate scaling is important to achieve acceptable product quality without compromising titer. Scale-down approaches involve matching the oxygen transfer coefficient (kLa) value, impeller tip speed, power per unit volume, or mixing time to those of a bioreactor. Bench-top bioreactors are typically used in bioprocess engineering as scale-down models of commercial units in fermentation and cell culture because of their similarity in geometry (H/D ratio) and mechanical properties (agitation type and sparging). By contrast, shaking culture systems such as Wave bioreactor, shake flasks, and tube spins are typically used for culture expansion. Significant improvements to the composition, shape, size and caps of shake flasks have facilitated sufficient oxygen transfer and mixing. Such modifications have allowed for use of shake flasks in production cultures for clone evaluation, media development, and process optimization.