Biomedical Engineering Reference
In-Depth Information
Figure 22.6.
SEM photomicrograph of a PLLA-collagen hybrid braid.
PLLA braid provides high mechanical properties, while collagen
microsponges provide good cell interaction with the hybrid braid.
Cellular responses of ligament cells to the PLLA and PLLA-collagen
hybrid braids were evaluated both
in vitro
and
in vivo
. More cells
andgreaterhomogeneouscelldistributionwereobserved
in vitro
in
thehybridbraidthaninthePLLAbraid.Greaterfibroblastimmigra-
tion and neoangiogenesis were detected in the hybrid braid than in
thePLLAbraidwhenimplantedonarupturedmedialcollateralliga-
ment(MCL).Hybridizationwithcollagenfacilitatedcellseedingand
spatial cell distribution and promoted cell immigration and neoan-
giogenesis.
22.5 Biphasic Hybrid Porous Scaffold
A biphasic scaffold composed of an upper layer of a collagen sponge
and a lower layer of a PLGA-collagen hybrid sponge has been
reported for tissue engineering of osteochondral tissue.
21
At first, a
biodegradable PLGA sponge cylinder was prepared by the porogen
leaching method using NaCl particulates. Then, a collagen/PLGA-
collagen biphasic sponge cylinder was prepared by introducing a
collagenspongeintotheporesofthePLGAspongeandformingacol-
lagen sponge on one side of the PLGA sponge (Fig. 22.7). One layer
of the biphasic scaffold was a highly porous collagen sponge. The
Search WWH ::
Custom Search