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International Journal of Bioprinting 3D-printed PCL-MNP multifunctional scaffolds

For successful bone tissue regrowth and overall scaffolds had less viability in comparison to the 10% MNP
scaffold success, the scaffold must possess certain scaffolds, the results were still satisfactory for biological
desirable properties. The printed PCL-MNP composite applications. Moreover, these scaffolds were tested for their
scaffolds were validated using a series of thermal, ability in cancer management via hyperthermia treatment.
magnetic, and mechanical tests to benchmark their Indeed, one of the key needs for postoperative tumor
performance against existing scaffolds. Firstly, the resection is to prevent tumor recurrence by eliminating
chemical composition of the scaffold is evaluated using any residual tumor cells. This has led to a demand for a
FTIR. The peaks on the spectrum are within the expected minimally invasive and targeted implant that can keep the
range and accurately depict the C–H bond vibration. tumors at bay by killing them in vivo upon the application
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However, the presence of magnesioferrite MNPs is of an AMF. Figure 6B features the AB cell viability results
validated through the Fe–O bond vibration. As the for scaffolds seeded with hMSCs and bone cancer cells
concentration of the MNPs increases, so does the peak at two different time points, i.e., before applying the
sharpness. The magnetization curves also reflect the AMF and after applying the external magnetic field. The
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concentration of MNPs present in the scaffold. With an temperature increase in the 50% MNP scaffold due to the
increase in the MNP concentration, the hysteresis curve magnetic field stimulus led to a statistically significant
of magnetization increases under the application of an decrease in the viability of bone cancer cells. Furthermore,
external magnetic field. The magnetization property of even the pure PCL scaffold demonstrated a decrease in
the scaffold is important because it determines the ability cancer cell proliferation, which can be attributed to the
of the scaffolds to efficiently target cancer tumors and heat conduction between the adjacent vials, leading to a
prevent their recurrence. In contrast to isolated cancer lack of perfect insulation. These results are in line with the
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therapies, the side effects are decreased when tumors existing literature.
are properly targeted. Thermal analysis in the form of Prevention of recurring tumors is a challenging
TGA and DSC enables us to determine the condition of problem. Thus, using MNPs that are uniformly dispersed
the scaffold implant under hyperthermia temperatures. throughout the polymer matrix led to a more uniform
Since the DSC of the scaffolds reports that the melting heating effect under an AMF. This leads to a more effective
point of PCL is above 50°C, it confirms that the PCL- hyperthermia effect, as uniform heating requires a lower
based scaffolds are suitable for hyperthermia treatment. hyperthermia temperature and reduces the significance
As the temperature increases, the thermogram displays of scaffold orientation compared to scaffolds with a
a sharp decrease above a certain temperature until a non-uniform distribution of heating elements. While
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saturation point is reached. Since the PCL chains present the heating effect is proportional to the strength of the
in the scaffold degrade into components like CO and magnetic field, it is also affected by the size and shape
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CO , the remaining weight at saturation is entirely due of the MNPs. Numerous in vitro and in vivo tests have
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2
to the presence of residual MNPs. These MNPs, while displayed cell death between 41 and 47 C. 50,51 High fever is
o
ideally directly proportional to MNP concentration in known to reach temperatures similar to mild hyperthermia,
the scaffold, sometimes display anomalous results due to but the difference is that hyperthermia locally targets the
uneven distribution of the nanoparticles in the scaffold tumor without affecting the surrounding cells and tissues,
matrix. Finally, the scaffold matrix was reinforced with while high fever triggers the body’s immune response and
an MNP concentration as high as 50%, which is a step ends up protecting the tumor along with the rest of the
up from other works in the literature that typically body. Thus, PCL scaffolds reinforced with 50% MNPs
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fabricated scaffolds with an MNP concentration of less display a temperature rise above 41°C under the magnetic
than 15%. field stimulus, which is ideal for hyperthermia, as the
While the success of the composite scaffold is dependent temperature facilitates cell death, but remains below the
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upon its thermal, magnetic, and mechanical properties, melting point of PCL. Furthermore, these advantageous
ultimately it needs to be suitable for biological applications. properties, coupled with the degradation rates of the
In order to evaluate the cell viability of these scaffolds, they PCL-MNP scaffolds, allow for multiple instances of
were seeded with hMSCs, and their growth was observed hyperthermia treatment.
using AB cell viability analysis. The analysis revealed While this work is a promising indicator in the
statistically significant cell proliferation observed for all fabrication of multi-functional scaffolds, it still has some
concentrations of the scaffolds. This is in concordance limitations. MNPs tend to agglomerate, making it difficult
with other results in the literature that report MNPs to achieve a uniform mixture in the solution. This lack
imparting superior cell proliferation and differentiation of uniformity can lead to wide variations in the results,
characteristics to the scaffolds. While the 50% MNP resulting in high standard deviations. Lack of insulation in
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Volume 10 Issue 6 (2024) 402 doi: 10.36922/ijb.4538