3D Printing of Bioactive Gel-like Double Emulsion into a Biocompatible Hierarchical Macroporous Self-Lubricating Scaffold for 3D Cell Culture

Abstract

The interconnected hierarchically porous structures are of key importance for potential applications as substrates for drug delivery, cell culture, and bioscaffolds, ensuring cell adhesion and sufficient diffusion of metabolites and nutrients. Here, encapsulation of a vitamin C-loaded gel-like double emulsion using a hydrophobic emulsifier and soy particles was performed to develop a bioactive bioink for 3D printing of highly porous scaffolds with enhanced cell biocompatibility. The produced double emulsions suggested a mechanical strength with the range of elastic moduli of soft tissues possessing a thixotropic feature and recoverable matrix. The outstanding flow behavior and viscoelasticity broaden the potential of gel-like double emulsion to engineer 3D scaffolds, in which 3D constructs showed a high level of porosity and excellent shape fidelity with antiwearing and self-lubricating properties. Investigation of cell viability and proliferation using fibroblasts (NIH-3T3) within vitamin C-loaded gel-like bioinks revealed that printed 3D scaffolds offered brilliant biocompatibility and cell adhesion. Compared to scaffolds without encapsulated vitamin C, 3D scaffolds containing vitamin C showed higher cell viability after 1 week of cell proliferation. This work represented a systematic investigation of hierarchical self-assembly in double emulsions and offered insights into mechanisms that control microstructure within supramolecular structures, which could be instructive for the design of advanced functional tissues.

A smart thermoresponsive macroporous 4D structure by 4D printing of Pickering-high internal phase emulsions stabilized by plasma-functionalized starch nanomaterials for a possible delivery system

“…The CLSM images also agree well with the droplet size distributions of the HIPEs, with flocculation being apparent in the emulsion stabilized by etherified SNCs or SNPs. It is worth mentioning that If droplets in this system remain physically stable against coalescence, then the resulting network formed by the flocculated oil droplets can offer strong viscoelastic property ( Shahbazi et al, 2023b ).…”

“…In a specific grid geometry, the square shape shows a high precision with a Pr of 1. In this case, Pr < 1 presents a round shape and Pr > 1 denotes an irregular shape ( Shahbazi et al, 2023b ). Based on the quantification results, the Pr of E–SNC–N and E-SNP-N was found to be 1.22 ± 0.09 and 1.19 ± 0.13, respectively.…”

“…While the large macropores originated via 3D printing, the hierarchically macroporous structures could be mainly induced by solvent evaporation. Here, oil droplets acted as the sacrificial template for macropores, which were developed upon the solvent removal ( Shahbazi et al, 2023b ). They also offered a uniform structure in terms of orientation and shape of spaces.…”