Liquid deposition modeling (LDM) is an evolving three-dimensional (3D) printing approach that mainly utilizes polymer solutions to enable the fabrication of biomedical scaffolds under mild conditions. A deep understanding of the rheological properties of polymer printing inks and the features of yielded scaffolds are critical for a successful LDM based fabrication of biomedical scaffolds. In this work, polymer printing inks comprised of Poly(epsilon-caprolactone) (PCL), sodium chloride (NaCl), and trichloromethane (CHCl3) were prepared. The rheological properties, including extrudability (shear stress, viscosity, and shear-thinning) and self-supporting ability (viscosity) of all printing inks were analyzed. Then printing performance was evaluated by measuring the…
Repairing massive rotator cuff tendon defects remains a challenge due to the high retear rate after surgical intervention. 3D printing has emerged as a promising technique that enables the fabrication of engineered tissues with heterogeneous structures and mechanical properties, as well as controllable microenvironments for tendon regeneration. In this study, we developed a new strategy for rotator cuff tendon repair by combining a 3D printed scaffold of polylactic-co-glycolic acid (PLGA) with cell-laden collagen-fibrin hydrogels. We designed and fabricated two types of scaffolds: one featuring a separate layer-by-layer structure and another with a tri-layered structure as a whole. Uniaxial tensile tests…
3D printing/bioprinting are promising techniques to fabricate scaffolds with well controlled and patient-specific structures and architectures for bone tissue engineering. In this study, we developed a composite bioink consisting of silk fibroin (SF), gelatin (GEL), hyaluronic acid (HA), and tricalcium phosphate (TCP) and 3D bioprinted the silk fibroin-based hybrid scaffolds. The 3D bioprinted scaffolds with dual crosslinking were further treated with human platelet-rich plasma (PRP) to generate PRP coated scaffolds. Live/Dead and MTT assays demonstrated that PRP treatment could obviously promote the cell growth and proliferation of human adipose derived mesenchymal stem cells (HADMSC). In addition, the treatment of PRP…
Supplying oxygen to inner areas of cell constructs to support cell proliferation and metabolism is a major challenge in tissue engineering involving stem cells. Developing devices that incorporate oxygen release materials to increase the availability of the localized oxygen supply is therefore key to addressing this limitation. Herein, we designed and developed a 3D-printed oxygen-releasing device composed of an alginate hydrogel scaffold combined with an oxygen-generating biomaterial (calcium peroxide) to improve the oxygen supply of the microenvironment for culturing adipose tissue-derived stem cells. The results demonstrated that the 3D-printed oxygen-releasing device alleviated hypoxia, maintained oxygen availability, and ensured proliferation of…