Detalhes do Documento

Knee meniscus lesions are a common injury that significantly impact an individual's quality of life. Meniscus tissue lack of intrinsic regenerative capacity requests efficient treatments that simultaneously offer robust mechanical integrity and promote rapid tissue integration. Current treatments fail in long-term, accelerating osteoarthritic changes in the knee [1]. To address the inherent trade-off between strength and bioactivity, this study employs a coaxial printing technique to fabricate core–shell constructs, where the core ink provides robust mechanical strength, and the shell ink enhances biological function. The coaxial technique enabled the simultaneous extrusion of two distinct inks through a single nozzle, creating a 3D strand composed by a core and a shell. This strategy allowed the combination of two materials: the core, composed of poly(-caprolactone) (PCL), a synthetic polymer that provides mechanical stability; and the shell, composed of silk fibroin (SF), a natural biopolymer that enhances cell attachment and long-term viability. Rheology tests were performed, and 3D printed implants were produced and analyzed in terms of morphology and mechanical performance. The in vitro biological properties were assessed through cell metabolic activity, proliferation, and microscopic imaging. The developed coaxial inks showed adequate rheological properties for printability and structural fidelity. Scanning electron microscopy (SEM) analysis confirmed the morphological characteristics and confirmed the distinct core–shell architecture of the printed constructs. Uniaxial tensile and compressive tests revealed robust mechanical properties, with obtained elastic modulus values within the physiological range. In vitro biological assays, performed with human primary fibrochondrocytes, showed that the SF shell significantly enhanced initial cell adhesion and long-term viability. Overall, this novel coaxial ink presented both enhanced mechanically and biologically performance, making it a promising candidate for 3D printing of personalized meniscus implants.