Hydrodynamics in Porous Media with Applications to Tissue Engineering - Porous Media: Applications in Biological Systems and Biotechnology - page 90

(e)

(c)

(b)

(a)

(d) (f )

: Implant or cultivated cells : Movement (media flow) : Culture media

FIGURE 3.4
Diagram of bioreactors classically used in tissue engineering. (a) Stirred flask
bioreactor: implants are attached to a fixed wire, a stirring rod mixing the
culture media (Malda et al. 2004; Sucosky et al. 2004; Lewis et al. 2005;
Bilgen et al. 2005; 2006); (b) fluidized bed bioreactor: implants are placed
within the cylindrical body of the bioreactor, the culture media flows from
the bottom to the top of the bioreactor (imposed flow rate) (David 2002;
Janssen et al. 2006); (c) rotating bioreactor: implants are placed within the
cylindrical body of the bioreactor, which rotates around its axis (Botchwey
et al. 2001, 2003, 2004; Singh et al. 2005); (d) hollow fiber bioreactor: implants
or cells are confined within the fibers, the culture media flows around the fibers
(Dulong and Legallais 2005); (e) perfusion bioreactor: the implant is attached
to the body of the bioreactor and is perfused by the culture media (imposed
flow rate) (Goldstein et al. 2001; Raimondi et al. 2002; Cartmell et al. 2003;
Sikavitsas et al. 2003); (f) parallel-plate bioreactor (or microfluidic bioreactor):
the implant is growing on the lower surface of the bioreactor, the culture
media flows between the upper surfaces of the implant and the bioreactor
(imposed flow rate) (Gemmiti and Guldberg 2006; Leclerc et al. 2006; Zhao
et al. 2007).

2005, 2006), the “fluidized bed bioreactors” (David 2002; Janssen et al . 2006),
or the “rotating bioreactors” (Botchwey et al . 2001, 2003, 2004; Singh et al .
2005). For those bioreactors, the flow (and, as a result, the associated convec-
tive transport) will occur or not within the implant depending on the value of
the pressure gradient imposed by the flow at the scale of the implant, on the
one hand, and the hydraulic permeability of the implant, on the other. Such
a characteristic parameter of the medium micro architecture has dimension of
length square and an order of magnitude approaching the pore radius squared.