Page 549 - IJB-9-6

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

the calcium magnesium phosphate (CMP) bio-ceramics, a of surface and biological properties can be achieved for the
combined phosphate of magnesium and calcium, have not enhanced spatial organization of cells within the composite
been thoroughly studied. Therefore, our strategy in this scaffold.
study is to first develop an optimal composition of CMP
bioceramic powder. Our second strategy is to develop a 2. Materials and methods
slurry of ceramic powder and PCL in a good organic solvent Poly(ε-caprolactone) pellets (PCL, Mw = 43,000 g/mol) with a
that is suitable for three-dimensional (3D) printing. Third, melting point of 58 – 64°C were purchased from Polysciences
we optimize the properties of the 3D-printed scaffolds so Inc. (Warrington, PA, USA). 2,2,2-Trifluoroethanol (TFE)
that the methodology and knowledge gained from this was purchased from Sigma-Aldrich (St. Louis, Mo, USA).
research will be applied for bone TE applications in the Magnesium oxide (MgO) nanopowder (size < 50 nm) and
future. calcium phosphate monobasic were purchased from Sigma

Additive manufacturing (AM) techniques enable Aldrich (St. Louis, MO, USA). Dulbecco’s modified Eagle’s
the fabrication of complex geometry scaffolds for TE medium (DMEM) was purchased from Life Technologies
applications [42-44] . 3D bioprinting enables the fabrication (Grand Island, NY, USA). The Alamar Blue and lactate
of tissue or organs using biomaterials and cells in a layer- dehydrogenase (LDH) assay kits were purchased from
by-layer fashion from the bottom up using computer- Thermo-scientific (Waltham, MA or Florence, KY).
aided design (CAD) model data . The three main 2.1. Synthesis of CMP bioceramics
[45]
fundamental approaches 3D bioprinting is based on
are as follows: (i) biomimicry, (ii) autonomous self- CMP ceramic was prepared using a mixture of MgO and
assembly, and (c) mini tissue building blocks. Different calcium phosphate monobasic according to a previously
[56]
types of AM techniques that can be used for bioprinting published paper . MgO was first dissolved in water,
include extrusion-based printing, inkjet-assisted printing, and calcium phosphate was added with a 2:1 molar ratio
and droplet-based printing [46,47] . The extrusion 3D (3.2:1 w/w). The mixture was vortexed for 5 min and
printing process is the most popular technique. With 3D then poured into a Petri dish. The Petri dish was kept in
bioprinting, complex tissue structures that mimic the fine a fume hood for 24 h to dry up all water from the mixer.
shape and size of the targeted natural original tissue can Fine powder of the CMP was stored in a desiccator. Four
be fabricated with personalized features. The applicability concentrations of the polymer and ceramic material in
of 3D bioprinting to biomedical devices, pharmaceutics, different proportions were formulated for the subsequent
and regenerative medicine has increased as a result experiments.
of recent breakthroughs in reinforcement strategies, 2.2. Production of PCL/CMP suspension
hydrogel chemistries, and crosslinking techniques .
[48]
Biocompatibility of the material being used, growth Initially, 50% (w/v) PCL was prepared by suspending 5 g
factor distribution, perfusion, and cell sensitivity to the of PCL pellets in 10 mL of TFE and ultra-sonicated at
printing procedures are some of the crucial aspects of 45°C for 2 h to produce PCL-only scaffolds. To produce
bioprinting, that must be taken into consideration because PCL-CMP composite scaffolds, the predetermined content
3D bioprinting works with living organisms such as cells of the CMP (5, 10, and 15 wt % in relation to the PCL
and tissues . In the past decade, numerous research polymer) was dispensed into 10 mL of TFE through ultra-
[49]
studies have been reported on optimizing AM techniques sonication at 45°C for 2 h. The experimental procedure to
for 3D scaffold fabrication with desired mechanical and produce PCL-CMP suspension is illustrated in Figure 1.
biological properties for cell growth in regenerative Pellets of PCL (5 g) were added to the TFE solvent
medicine [50-55] . In this research, we utilized the direct-write containing the CMP and then mixed using magnetic
AM technique to fabricate a composite scaffold with CMP stirring for 24 h. Similarly, PCL-CMP composites with
bio-ceramic and PCL materials for bone TE application. In a CMP content of 10% and 15% were also prepared.
our experiments, four groups of scaffolds – PMC-0: PCL Each composition of the suspension is shown in Table 1.
(50% w/v), PMC-5: PCL (50% w/v)/CMP(5%w/w), A 100-mm filter was used to filter all the CMP solutions to
PMC-10: PCL (50% w/v)/CMP (10%w/w), and avoid clogging during printing.
PMC-15: PCL (50% w/v)/CMP (15%w/w) – were fabricated
using a custom-built 3D printer. The effect of ceramic 2.3. 3D printing of scaffolds
content on the surface properties, biodegradability, and A four-axis Nordson EFD Janome robot with a custom
bioactivity of fibroblast cells on the composite scaffold was extrusion head, as shown in Figure 2, was used to fabricate
investigated. A customized functionally gradient scaffold 3D scaffold structures. All material concentrations were
structure was fabricated to demonstrate that manipulation loaded into a 10 mL syringe barrel with a nozzle of 250 μm

Volume 9 Issue 6 (2023) 541 https://doi.org/10.36922/ijb.0196