Page 553 - IJB-9-6

International Journal of Bioprinting 3D printing of PCL-ceramic composite scaffolds

Figure 5. XRD pattern (left) and FT-IR spectra (right) of as-prepared CMP ceramic powder.
the band at 883.24 cm and 1164.8 cm correspond to
-1
-1
the vibration of P–O–H from Mg (PO ) and Ca (PO ) .
3
4 2
4 2
3
Adsorbed water band is relatively wide, from 2600 cm
-1
to 3600 cm . The additional band at 1648.85 cm was
-1 9
-1
observed due to H-O-H bending . These results indicate
[60]
that the chemical composition of CMP bioceramics has
both Ca and Mg phosphates.
3.3. Morphology analysis of 3D scaffolds
The morphology of the PCL and PCL-CMP composite
scaffolds was investigated with an SEM. Figure 6 presents
SEM micrographs of the top surface and cross-sectional
morphology of the PMC-0, PMC-5, PMC-10, and PMC-15
scaffolds, respectively.
The SEM images illustrate that all the scaffolds exhibit
well-defined structures with uniform pore size distribution.
The pore size of the polymer and composite scaffolds was
200 ± 35 μm, marginally less than the designed scaffold
(250 μm). The variations in the pore size are due to
the rheological characteristics of materials. Typically,
3D printing processes provide precise dimensions and
shapes of the features being printed. However, in this
case, the PCL-ceramic composite materials (PMCs) were
laden with solvent (TFE) to suit appropriate rheology for
extrusion from the nozzle tip. Thus, after the deposition Figure 6. The surface and cross-section morphology of PMC-0, PMC-5,
of these materials, there was a shrinkage after curing PMC-10, and PMC-15. Left: SEM images of 3D-printed scaffolds.
Right: SEM images showing the cross-sectional view of the scaffold’s
and evaporation of the water, leading to lower pore size single strut. The pore size of the composite scaffolds was in the range
as compared to the designed (250 μm) dimension. The of 200 ± 35 μm.
PCL scaffolds appear to have a smooth surface compared
to the PMC-5, PMC-10, and PMC-15. As the amount of cell adhesion and proliferation are porosity and surface
ceramic content increased, the surface morphology of roughness of the scaffold, as mentioned elsewhere [63-65] .
the composite scaffold exhibited a rough structure. The The rheological changes were tailored by adding ceramic
roughness of the composite scaffold surface is due to the microparticles, which altered the properties such as shear
dispersion of ceramic microparticles in the PCL matrix, stress, viscosity, and interaction between flow material
which alters the morphology of PCL. This leads to a rougher and nozzle wall. Hence, the PCL and composite scaffold
surface with an increased surface area that closely mimics surface characteristics reacted differently under similar
the natural ECM [61,62] . The crucial characteristics that affect process conditions.

Volume 9 Issue 6 (2023) 545 https://doi.org/10.36922/ijb.0196