plugs with modified surfaces for use as efficient cell culture media have been used
in continuous processing for production of urokinase (Figs. 4 and 5) [52] and
monoclonal antibodies [43, 53]. In this latter study, cryogel that was surface
modified (also within the pores) with gelatin was produced within plastic housings
Fig. 2 SEM images of gels prepared from N-isopropyl acrylamide (NIPA) or bacterial suspensions. (a, b) Prepared gel of a 5 % (w/v) NIPA particle suspension at À12
C that was crosslinked
with 20 μL glutaraldehyde, shown at low and high magnification. (c) Prepared gel of a 10 % (wet
weight/volume) C. saccharolyticus suspension at À12
C that was crosslinked with 10 μL
glutaraldehyde. (d) 15 % (wet weight/volume) C. saccharolyticus and S. cerevisiae suspension
(ratio 10:1 w/w) crosslinked with 10 μL glutaraldehyde at –12
C; arrow indicates S. cerevisiae
incorporated into the structure. (e) 10 % (wet weight/volume) E. coli gel. (f) 15 % (wet weight/
volume) Ralstonia eutropha gel; both samples (e) and (f) were prepared by crosslinking with 10 μL
of glutaraldehyde. All gels were prepared in 1 mL batches (From [45] with permission)
Cryogels for Biotechnological Applications
253