Multiphase Bioreactor Design

In this chapter empirical models describing the specific death rate due to sparging as a
function of reactor parameters are first discussed. Next, current knowledge on the
mechanism of cell death due to sparging is reviewed. For this it is necessary to have
knowledge of the mechanical properties of animal cells and the interaction of cells with
air bubbles, which are therefore discussed first. With this knowledge in mind, the
possible mechanisms of cell death are reviewed for different regions in the reactor; the

Table 15.1 Static surface tension σ0, dynamic

surface tension σd, surface viscosity

μ

s, and surface

dilatational viscosity ks of media with different

additives

Medium Cone
(%)

σo mN.

m−^1

σd

mN.m−^1

μs 10 –4

N.m−^2

ks 10 –4

N.m−^2

Ref.

HBBS 72.8 Chattopadhyay
1995b

RPMI 70 0.25 Dey 1997

TNM-FH 47.3 69.4 Chattopadhyay
1995b

SFM-L 64 Chattopadhyay
1995b

Serum free 61 70.8 5.1 0.46 Michaels 1995b

0.5 70.8 Michaels 1995b

0.5 54 Dey 1999

1.0 70.4 Michaels 1995b

3.0 68.9 18200 1.36 Michaels 1995b

5.0 69.2 Michaels 1995b

5.0 Michaels 1995b

5.0 52.4 1.5 Dey 1997

Serum

10.0 68.8 Michaels 1995b

0.1 48 57.6 2.4 0.37 Michaels 1995b

0.1 40 Dey et al. 1997

0.1 44.1 56.1 Chattopadhyay

1995b

Pluronic
F68

0.2 38 2 Dey 1997

Methocel 0.1 52 55.7 <0.1 Michaels 1995b
E50
0.3 66.1 55.5 Chattopadhyay
1995b

Lethal effects of bubbles in animal-cell culture 455