Environmental Engineering Reference
In-Depth Information
Fig. 7.2
General cell entrapment procedures
The gelation takes place via several processes including ionictropic gela-
tion, temperature-induced gelation, organic polymerization, and phase separation
depending on entrapment matrices [39]. Ionictropic gelation is a cross-linking
between a matrix (polyionic polymer) and a cation in the gel formation solution.
For example, calcium alginate is formed through ionictropic gelation. Temperature-
induced gelation is a phase transition at different temperatures. The examples of
the temperature-induced gelation are agarose and gelatin formations. Organic poly-
merization occurs through a reaction between monomers. Common cell entrapment
matrices such as polyacrylamide, polymethacrylate, and PVA are the products of
organic polymerization. During polymerization, a cross-linking agent may be added
for a better gel network. The last process is a phase separation which the cells are
