4D polycarbonates via stereolithography as scaffolds for soft tissue repair

3D printing has emerged as one of the most promising tools to overcome the processing and morphological limitations of traditional tissue engineering scaffold design. However, there is a need for improved minimally invasive, void-filling materials to provide mechanical support, biocompatibility, and surface erosion characteristics to ensure consistent tissue support during the healing process. Herein, soft, elastomeric aliphatic polycarbonate-based materials were designed to undergo photopolymerization into supportive soft tissue engineering scaffolds. The 4D nature of the printed scaffolds is manifested in their shape memory properties, which allows them to fill model soft tissue voids without deforming the surrounding material. In vivo, adipocyte lobules were found to infiltrate the surface-eroding scaffold within 2 months, and neovascularization was observed over the same time. Notably, reduced collagen capsule thickness indicates that these scaffolds are highly promising for adipose tissue engineering and repair.


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Policy information about availability of data All manuscripts must include a data availability statement. This statement should provide the following information, where applicable: -Accession codes, unique identifiers, or web links for publicly available datasets -A list of figures that have associated raw data -A description of any restrictions on data availability Andrew Dove 4th May 2021 RheoCompass ™ software (v1.20.496) was used for rheology on a Anton Paar Modular Compact Rheometer MCR302; STARe software (v10.00) was used for thermomechanical measurements on a STARe System DMA 1, Mettler Toledo; Solidworks software was used for stl file generation; SkyScan software (NRecon v1.6.2) was used to reconstruct microCT images into 3D structures. Sample processing was conducted using Origin v8 software (processing and figure generation) Statistical analysis has been performed on the thermomechanical analysis (DMA, tensile testing), rheology, gravimetric analysis, histopathological scoring and on the cell viability data using a two-way ANOVA test or a Welch's unpaired t test, with p < 0.05, analysed with GraphPrism 8 software.
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Life sciences study design
All studies must disclose on these points even when the disclosure is negative. 6 replications were used for each material at each time point (sample power greater than 80%, degrees of freedom above 10, 5% uncertainty) No data was excluded from analysis.
For cell studies: three independent experiments were performed for each sample. In each independent experiment, samples were replicated at least three times. All attempts at replication were successful. For animal studies: 6 replications were used for each material at each time point. All replications were successful.
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