Biomedical Engineering Reference
In-Depth Information
Figure 10.3.
Schematic diagrams of various collectors for aligned elec-
trospun fibers: (A) rotating drum,
22
,
23
(B) rotating wire drum, (C) rotating
drum with wire,
24
(D) parallel electrodes,
25
(E) rotating disk,
26
(F) knife-
edge electrode,
27
and (G)auxiliary electrode.
28
properly. Therefore, the use of electrospun scaffolds with aligned
nanofiberarchitecturewouldresultincellularalignment.Aconven-
tional collection of nanofibers on the surface of a rotating drum or
mandrelcansimplyproducealignedfiberswithhighrotationveloc-
ities. To achieve fiber alignment, the collector in the electrospin-
ning assembly must be correctly designed. Schematic diagrams of
various collecting substrates used for spinning aligned nanofibrous
assemblies are shown in Fig. 10.3. This type of geometric arrange-
ment would be appropriate for use in scaffold-based tissue engi-
neering, as the cells grow preferentially in the direction of the fiber
orientation.
A simple way to achieve uniaxial alignment in the nanofiber
deposition is to increase the rotational speed of the collector.
Figure 10.4 shows that nanofibrous scaffolds with different fiber
angles were produced by electrospinning at various rotation rates.
Progressive alignment of fiber orientation was observed as the
rotation rate increased. Histograms for orientation of electrospun
scaffolds indicate a close correlation between fiber distribution and
the wrapped normal distribution function.
Electrospun fiber orientation can influence cell proliferation,
in addition to controlling cell orientation and tissue growth. It is
Search WWH ::
Custom Search