Biomedical Engineering Reference
In-Depth Information
80
60
40
20
Alginate
Mixed
CPC
0
0
50
100
150
200
250
300
350
400
Time (hour)
FIGURE 4.14
BSA release from plotted scaffolds in SBF at 37°C over a period of 16 days.
released from the pure alginate scaffolds because of the high nanoporosity
of the hydrogel and quick degradation of alginate scaffolds as well as the low
protein binding capacity of alginate in general. Again, for the mixed algi-
nate-CPC scaffolds an intermediate release profile was detected. It can be
speculated that the release of proteins from biphasic CPC-alginate scaffolds
can be controlled by altering the loading amount of BSA in CPC and alginate
strands (Figure 4.14).
Our data demonstrate the beneficial effect of the combination of ceram-
ics and polymers by alternate extrusion that result in biphasic scaffolds.
Especially with respect to the mechanical properties the performance of the
biphasic CPC-alginate composite scaffolds exceed that of those fabricated
by 3D plotting of a mixed paste of CPC and alginate. In addition, the bipha-
sic CPC-alginate scaffolds performed better in first cell culture experiments
compared to the mixed ones.
Furthermore, by using the 3D plotting technique and a device that allows
the utilization of more than one pasty material for one scaffold, an upgraded
biphasic scaffold with separate layers suitable for repair of defects at tissue
interfaces can be developed (Figure 4.15). Such a complex scaffold could
be designed, for example, for an osteochondral defect, by combining an
organic/inorganic composite layer to fill the bony part of the lesion and a
non-mineralized organic layer for the repair of the chondral part. To ensure
that both layers are tightly connected to each other, they have to be plotted
simultaneously and some of the strands of the organic phase have to pen-
etrate the other (composite) layers realizing a mechanically stable interlock-
ing of both materials.
Search WWH ::
Custom Search