Highly resilient and fatigue-resistant poly(4-methyl-ε-caprolactone) porous scaffold fabricated via thiol-yne photo-crosslinking/salt-templating for soft tissue regeneration

Elastomeric scaffolds, individually customized to mimic the structural and mechanical properties of natural tissues have been used for tissue regeneration. In this regard, polyester elastic scaffolds with tunable mechanical properties and exceptional biological properties have been reported to provide mechanical support and structural integrity for tissue repair. Herein, poly(4-methyl-& epsilon;-caprolactone) (PMCL) was first double-terminated by alky-nylation (PMCL-DY) as a liquid precursor at room temperature. Subsequently, three-dimensional porous scaffolds with custom shapes were fabricated from PMCL-DY via thiol-yne photocrosslinking using a practical salt tem-plate method. By manipulating the Mn of the precursor, the modulus of compression of the scaffold was easily adjusted. As evidenced by the complete recovery from 90% compression, the rapid recovery rate of >500 mm min-1, the extremely low energy loss coefficient of <0.1, and the superior fatigue resistance, the PMCL20-DY porous scaffold was confirmed to harbor excellent elastic properties. In addition, the high resilience of the scaffold was confirmed to endow it with a minimally invasive application potential. In vitro testing revealed that the 3D porous scaffold was biocompatible with rat bone marrow stromal cells (BMSCs), inducing BMSCs to differentiate into chondrogenic cells. In addition, the elastic porous scaffold demonstrated good regenerative efficiency in a 12-week rabbit cartilage defect model. Thus, the novel polyester scaffold with adaptable me-chanical properties may have extensive applications in soft tissue regeneration.

Automated summary

Customized elastomeric scaffolds mimicking natural tissues have been used for tissue regeneration. Polyester elastic scaffolds with tunable mechanical properties have shown excellent elasticity and have potential applications in soft tissue regeneration.