Strategies To Modify the Surface and Bulk Properties of 3D-Printed Solid Scaffolds for Tissue Engineering Applications

Abstract

3D printing is one of the effective scaffold fabrication techniques that emerged in the 21st century that has the potential to revolutionize the field of tissue engineering. The solid scaffolds developed by 3D printing are still one of the most sought-after approaches for developing hard-tissue regeneration and repair. However, applications of these solid scaffolds get limited due to their poor surface and bulk properties, which play a significant role in tissue integration, loadbearing, antimicrobial/antifouling properties, and others. As a result, several efforts have been directed to modify the surface and bulk of these solid scaffolds. These modifications have significantly improved the adoption of 3D-printed solid scaffolds and devices in the healthcare industry. Nevertheless, the in vivo implant applications of these 3D-printed solid scaffolds/devices are still under development. They require attention in terms of their surface/bulk properties, which dictate their functionality. Therefore, in the current review, we have discussed different 3D-printing parameters that facilitate the fabrication of solid scaffolds/devices with different properties. Further, changes in the bulk properties through material and microstructure modification are also being discussed. After that, we deliberated on the techniques that modify the surfaces through chemical and material modifications. The computational approaches for the bulk modification of these 3D-printed materials are also mentioned, focusing on tissue engineering. We have also briefly discussed the application of these solid scaffolds/devices in tissue engineering. Eventually, the review is concluded with an analysis of the choice of surface/bulk modification based on the intended application in tissue engineering.

From Waste to Filament: Development of Biomass-Derived Activated Carbon-Reinforced PETG Composites for Sustainable 3D Printing

“…However, the rigidity, plastic deformation limit, and mechanical strength of activated carbon-infused PETG are ∼30% higher than pure PETG samples as measured by their significantly higher Young’s modulus, yield strength, and ultimate strength, respectively (Figure B). The increased mechanical strength of AC-PETG30 samples can be explained by the presence of −CH groups in the FTIR spectra of AC-PETG30 which indicate that the complex carbon chains of activated carbon have been successfully introduced into the PETG polymer matrix . While, in the case of AC-PETG30, due to the higher crystallinity of the compound compared to hydrochar as evidenced by the XRD analysis, a more significant interfacial adhesion between the filler and matrix can occur, which further reinforces the mechanical strength of the composite .…”

“…The increased mechanical strength of AC-PETG30 samples can be explained by the presence of −CH groups in the FTIR spectra of AC-PETG30 which indicate that the complex carbon chains of activated carbon have been successfully introduced into the PETG polymer matrix. 56 While, in the case of AC-PETG30, due to the higher crystallinity of the compound compared to hydrochar as evidenced by the XRD analysis, a more significant interfacial adhesion between the filler and matrix can occur, which further reinforces the mechanical strength of the composite. 57 Finally, the smaller cracks and deformation observed in the SEM images of the AC-PETG30 sample also suggest their higher mechanical strength.…”

Surface Modification of Polylactic Acid Bioscaffold Fabricated via 3D Printing for Craniofacial Bone Tissue Engineering

“…The 3D printing technique offers an effective way to fabricate scaffolds for tissue engineering, and these 3DP scaffolds are one of the most promising approaches for hardtissue regeneration and repair [63][64][65]. PLA provides desirable characteristics for tissue engineering, but there are limitations stemming from their poor surface properties, bulk properties, hydrophobicity, and lack of recognizable biochemical binding sites, which are necessary for cell-surface interaction [37,63]. To overcome these problems, many efforts have been directed at modifying the surface of the scaffolds, and hydrogels with advanced biomaterial characteristics are one of the solutions [37].…”

Recent trends in bone tissue engineering: a review of materials, methods, and structures

“…By promoting favorable interactions between cells and the substrate, hydrophilic surfaces play a critical role in enhancing the success of tissue regeneration strategies. Hydrophilicity of scaffolds can be controlled by affected factors such as bulk material, processing method, shape, surface roughness, surface modification, and so forth [200][201][202][203]. For instance, in electrospun nanocomposites of polyhydroxybutyrate/starch/MWCNTs, results showed that MWCNTs had a positive effect on decreasing the fiber diameter and improving the mechanical properties, surface roughness and hydrophilicity.…”