3.1 Polymeric
Mixtures Preparation
1. For the fabrication of PCL80 0.5 scaffolds, add 400 mg of PCL
to acetone in a 10 mL glass flask, and left the mixture at 35
C
under gentle magnetic stirring for 3 h in order to prepare 5 mL
of a homogenous solution at 8% w/v concentration (see
Note 2).
2. For the fabrication of PCL80/HA 0.5 composite scaffolds, add
80 mg of HA to a PCL solution prepared as described in step 1,
and left the suspension at 35
C under vigorous stirring for 2 h
to achieve a homogeneous dispersion.
3.2 Scaffold
Fabrication
The sequential steps for the fabrication of PCL80 0.5 and PCL80/
HA 0.5 scaffolds are following described.
1. Set the optimized lay-down parameters as following reported:
(1) d xy ¼ 0.5 mm; (2) V dep ¼ 170 mm/min; (3) d z ¼ 0.2 mm
(see Notes 3 and 4).
2. Place the PCL solution or PCL/HA mixture in a plastic syringe
(10 mL volume), and mount a blunt tip stainless steel needle
(gauge 23) on it (see Notes 5 and 6).
3. Place the syringe in the programmable syringe pump mounted
on the AM machine (see Note 7).
4. Fix a clean glass beaker on the deposition platform (see
Note 8).
Table 2
Optimized parameters for the fabrication of polyester-based scaffolds by CAWS
Sample
a
d XY (mm)
d Z
(mm)
V dep
(mm/min)
F sol
(mL/h)
Z 0
(mm)
Needle gauge
(inner diameter) Ref.
PCL80 1
PCL80/HA 1
1.0
b
0.2
300
1.4
5.0
23 (0.34 mm)
[4]
PCL80 0.5
PCL80/
HA 0.5
0.5
0.2
170
1.0
1.0
23 (0.34 mm)
[4]
PCL50
PCL50/HA
0.5, 1.0, 1.5,
2.0
0.1
240
1.0
2.0
22 (0.41 mm)
[5]
∗PCL
∗PCL/HA
0.5
0.2
240
1.0
1.0
23 (0.34 mm)
[6]
PHBHHx
1.0, 0.5 (0.2)
c
0.1
600
0.5 (0.3)
c 2.0
22 (0.41 mm)
[10]
d XY interfiber needle translation; d Z interlayer needle translation; V dep resulting needle translation velocity; F sol solution
feed rate; Z 0 initial needle tip-deposition plane distance
a
In all cases, ethanol was used as non-solvent
b
0.5 mm staggered fiber spacing between successive layers with the same fiber orientation was adopted (see Note 3)
c
In the case of d xy ¼ 0.2 mm, the optimized value of F sol was 0.3 mL/h
106
Dario Puppi and Federica Chiellini
Mixtures Preparation
1. For the fabrication of PCL80 0.5 scaffolds, add 400 mg of PCL
to acetone in a 10 mL glass flask, and left the mixture at 35
C
under gentle magnetic stirring for 3 h in order to prepare 5 mL
of a homogenous solution at 8% w/v concentration (see
Note 2).
2. For the fabrication of PCL80/HA 0.5 composite scaffolds, add
80 mg of HA to a PCL solution prepared as described in step 1,
and left the suspension at 35
C under vigorous stirring for 2 h
to achieve a homogeneous dispersion.
3.2 Scaffold
Fabrication
The sequential steps for the fabrication of PCL80 0.5 and PCL80/
HA 0.5 scaffolds are following described.
1. Set the optimized lay-down parameters as following reported:
(1) d xy ¼ 0.5 mm; (2) V dep ¼ 170 mm/min; (3) d z ¼ 0.2 mm
(see Notes 3 and 4).
2. Place the PCL solution or PCL/HA mixture in a plastic syringe
(10 mL volume), and mount a blunt tip stainless steel needle
(gauge 23) on it (see Notes 5 and 6).
3. Place the syringe in the programmable syringe pump mounted
on the AM machine (see Note 7).
4. Fix a clean glass beaker on the deposition platform (see
Note 8).
Table 2
Optimized parameters for the fabrication of polyester-based scaffolds by CAWS
Sample
a
d XY (mm)
d Z
(mm)
V dep
(mm/min)
F sol
(mL/h)
Z 0
(mm)
Needle gauge
(inner diameter) Ref.
PCL80 1
PCL80/HA 1
1.0
b
0.2
300
1.4
5.0
23 (0.34 mm)
[4]
PCL80 0.5
PCL80/
HA 0.5
0.5
0.2
170
1.0
1.0
23 (0.34 mm)
[4]
PCL50
PCL50/HA
0.5, 1.0, 1.5,
2.0
0.1
240
1.0
2.0
22 (0.41 mm)
[5]
∗PCL
∗PCL/HA
0.5
0.2
240
1.0
1.0
23 (0.34 mm)
[6]
PHBHHx
1.0, 0.5 (0.2)
c
0.1
600
0.5 (0.3)
c 2.0
22 (0.41 mm)
[10]
d XY interfiber needle translation; d Z interlayer needle translation; V dep resulting needle translation velocity; F sol solution
feed rate; Z 0 initial needle tip-deposition plane distance
a
In all cases, ethanol was used as non-solvent
b
0.5 mm staggered fiber spacing between successive layers with the same fiber orientation was adopted (see Note 3)
c
In the case of d xy ¼ 0.2 mm, the optimized value of F sol was 0.3 mL/h
106
Dario Puppi and Federica Chiellini