LAUSR

Bioprinting is an emerging technology for fabricating cell-laden scaffolds with custom shapes and patterns that resemble the complex architecture of human tissues, however, construction of mechanically competent tissue grafts which mimic irregular cartilage defect is still a big challenge. Here we report 3D printing of short fiber-reinforced double-network bioink to generate anatomically accurate and mechanical tunable scaffold for cartilage regeneration. Poly (lactic acid) (PLLA) short fibers were firstly prepared by electrospinning and then fragmented through aminolysis reaction. Composite inks were constructed with incorporation of fragmented microfibers with varied amounts and lengths into oxidized alginate bioink. Our results showed that incorporation of PLLA short fibers not only improved the printing fidelity but also facilitated in generating mechanically strong constructs. By incorporating GelMA and optimizing the bioink composition, the fabricated constructs with a compressive stress of ∼150 KPa even after 100 cyclical compression loading (up to 40% of strain) were achieved. In addition, this mechanically reinforced alginate/GelMA double-network bioink displayed good biocompatibility and supported bone marrow derived stromal cell chondrogenesis in vitro. Collectively, our findings demonstrate this approach was capable of printing engineered grafts which resemble the irregular size and mechanical properties of cartilage and thus hold potential for functional tissue regeneration. This article is protected by copyright. All rights reserved.