Tailor-Made and Biodegradable Vascular Scaffolds - Microsurgery: Advances, Simulations, and Applications - page 271

For porous PLCL scaffolds, we conirmed that Young's modulus
depends on the porosity and concentration of PLCL in chloroform.
Table 8.1 and Fig. 8.6 show the relationship between Young's
modulus and porosity (i.e., the weight ratio between NaCl and PLCL)
and the concentration of PLCL in chloroform. These data indicate
that Young's modulus for PLCL scaffolds was larger in scaffolds with
lower porosity and higher PLCL concentration, and was controllable
from 0.6 to 5.2 MPa.

Stretch speed: 0.1 mm/s
Number of samples: 3

Dip coater

6

PLCL 10% in Chloroform
PLCL 5% in Chloroform
PLCL 3% in Chloroform

5

4

Load cell 3

2

1

0

Force gage

0 20 40 60 80

Laptop

NaCl ratio in PLCL (w%)

Figure 8.6 Environment of tensile tests by using a dip-coater as a stretching

apparatus (Left). Relationship between polymer composition,
porosity and Young's moduli of sheet-like scaffolds (Right).

8.5 Spatial Distribution of Pores Inside

Scaffolds

We also evaluated the spatial distribution of pores inside four kinds
of scaffolds shown in Fig. 8.7. Scaffolds were fabricated from polymer
solution (PLCL 5% in chloroform) with four different composition of
sodium chloride (NaCl : PLCL = 2 : 8, 4 : 6, 6 : 4, 8 : 2 in weight %). Dip
coating of polymer solution on the tube models was operated 12 times
(6 times to one direction and another 6 times to inverse direction) at
the pull-up speed of 1 mm/s. Based on the schematic shown in Fig.
8.8, the fabricated scaffolds were cut and divided into three parts
to evaluate spatial distribution of porosity. Figure 8.9 shows optical
images of porous coniguration at four kinds of scaffolds. These
images show cross-sectional and surface coniguration at the middle
of scaffold (Part B in Fig. 8.9). Porous structure was conirmed all
over the scaffold at every kind of scaffolds.