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International Journal of Bioprinting Bioprinting for wearable tech and robot

been crucial for optimizing bioprinting processes and integrity, affecting shape fidelity post-printing and during
creating superior biological constructs. Characteristics in vitro culture or in vivo implantation. 46
of materials, such as viscosity, morphology, and Synthetic polymers are engineered polymeric materials
biocompatibility, govern the technological advancement that offer a broader range of mechanical properties and
and improvements in bioprinting. The selection or degradation profiles. Moreover, their specific mechanical
design of materials with suitable properties has become strength, elasticity, and biodegradability make them highly
increasingly significant to ensure successful bioprinting. versatile in fabricating scaffolds for tissue engineering.
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Of these, cells and the extracellular matrix (ECM) are Synthetic polymers can be customized for specific
the most commonly used and fundamental materials applications and degrade at controlled rates, allowing
in bioprinting, while hydrogels and synthetic polymers temporal control over scaffold stability. It is crucial to tailor
serve as essential supporting materials. Likewise, polymerization and crosslinking processes to minimize
nanocomposites and bioactive materials are considered residual monomers and potentially harmful additives
functional modulatory components. and to precisely control the degradation rates of synthetic
2.2.1. Cells and extracellular matrix components polymers to match tissue kinetics. 48
Cells and ECM components are distinct bioprinting 2.2.3. Nanocomposites
materials that confer numerous advantages. Cells serve Nanocomposites incorporate nanoparticles into a bulk
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as functional units that drive tissue development and matrix to enhance its physical and chemical properties. In
function. Bioprinting enables the precise positioning 3D printing, they offer enhanced mechanical properties,
of cells within 3D structures, allowing for the creation biocompatibility, and bioactivity. 49 Additionally,
of complex tissue architectures that can potentially nanocomposites can alter mechanical properties, such
recapitulate in vivo function. The ECM, a complex as strength, elasticity, and toughness, making them
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mixture of structural and functional molecules secreted suitable for a wide range of biomedical applications,
by cells, serves as a scaffold for cell adhesion, proliferation, including bone and dental implants. The presence of
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and differentiation. Bioprinting with ECM components nanoparticles within the matrix can significantly alter
produces tissues that closely resemble engineered surface characteristics, which is crucial for cell attachment
structures, with precise biomechanics and biochemical and proliferation. Furthermore, nanocomposites can be
content. Combining cells and ECM components in engineered for specific antibacterial properties, facilitating
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bioprinting facilitates the creation of functional tissues their application in patient-specific implants and devices
with biomimetic properties. in clinical settings. Several key considerations should
When using both components in bioprinting, several be addressed to ensure optimal performance and safety
factors should be considered, such as careful handling of when incorporating nanocomposites in bioprinting, such
live cells, maintaining correct temperature and a nutrient- as nanocomposite stability, as nanoparticles may shift or
rich environment, and suppressing immune responses to react under physiological conditions, affecting the long-
printed ECM components or cells in tissue engineering. term reliability of printed structures. 51
Therefore, sophisticated planning and a thorough
understanding of materials and techniques are essential for 2.2.4. Bioactive materials
creating complex, functional structures. 44 Bioactive materials are engineered to induce specific
biological reactions at their interface, developing a
2.2.2. Hydrogels and synthetic polymers connection between the material and living tissues.
Hydrogels are hydrophilic polymers with the ability to In bioprinting, the primary characteristic of bioactive
retain a substantial volume of water within their networks, materials is their ability to support cell adhesion,
and they are the most commonly used biomaterials proliferation, and differentiation. These materials often
in 3D bioprinting. Hydrogels feature a high degree of undergo surface modifications to enhance their bioactivity
biocompatibility, which minimizes negative immune and promote tissue repair. Additionally, their inherent
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responses upon implantation. Additionally, they provide a degradability allows for their gradual replacement by
soft and pliable consistency that resembles the texture of soft native tissues, thereby reducing the need for secondary
tissues. The porous structure of hydrogels also facilitates surgeries. Bioactive materials can be precisely printed
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efficient nutrient and waste exchange, making them ideal into complex, porous structures that mimic the natural
for tissue engineering applications that necessitate a ECM to support cell growth and vascularization, making
semblance to physiological conditions. Hydrogels face them particularly effective for creating scaffolds for bone
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challenges due to their high-water content and elasticity, and dental regeneration. However, employing bioactive
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which can limit their mechanical strength and structural materials in bioprinting demands careful consideration

Volume 10 Issue 6 (2024) 20 doi: 10.36922/ijb.3590