3D Bioplotter Research Papers

Creating tissue and organ equivalents with intricate architectures and multiscale functional feature sizes is the first step toward the reconstruction of transplantable human tissues and organs. Existing embedded ink writing approaches are limited by achievable feature sizes ranging from hundreds of microns to tens of millimeters, which hinders their ability to accurately duplicate structures found in various human tissues and organs. In this study, a multiscale embedded printing (MSEP) strategy is developed, in which a stimuli-responsive yield-stress fluid is applied to facilitate the printing process. A dynamic layer height control method is developed to print the cornea with a smooth…

In recent years, a new additive manufacturing (AM) method for three-dimensional (3D) syringe-extrusion (bio)printing of soft hydrogels has been introduced under the name of Freeform Reversible Embedding of Suspended Hydrogels (FRESH). The most common FRESH bath contains gelatin as the main compound and low concentrations of crosslinker(s) (whose nature depends on the hydrogel) for the initiation of an in-situ pre-crosslinking process during printing. In the case of sodium alginate (SA)-based hydrogels ionically crosslinked via calcium chloride (CaCl2), the crosslinker percentage in the gelatin bath is equal to ~10 mM, usually combined with a post-crosslinking at higher concentrations. However, according to the…

The emergence and innovation of three-dimensional (3D) bioprinting provide new development opportunities for tissue engineering and regenerative medicine. However, how to obtain bioinks with both biomimicry and manufacturability remains a great issue in 3D bioprinting. Developing intelligent responsive biomaterials is conducive to break through the current dilemma. Herein, a stepwise multi-cross-linking strategy concerning thermosensitive thiolated Pluronic F127 (PF127-SH) and hyaluronic acid methacrylate (HAMA) is proposed to achieve temperature-controlled 3D embedded bioprinting, specifically pre-cross-linking (Michael addition reaction) at low temperatures (4–20 °C) and subsequently self-assembly (hydrophobic interaction) in a high-temperature (30–37 °C) suspension bath as well as final photo-cross-linking (mainly thiol-ene…

Background There is a great clinical need and it remains a challenge to develop artificial soft tissue constructs that can mimic the biomechanical properties and bioactivity of natural tissue. This is partly due to the lack of suitable biomaterials. Hydrogels made from human placenta offer high bioactivity and represent a potential solution to create animal-free 3D bioprinting systems that are both sustainable and acceptable, as placenta is widely considered medical waste. A combination with silk and gelatin polymers can bridge the biomechanical limitations of human placenta chorion extracellular matrix hydrogels (hpcECM) while maintaining their excellent bioactivity.   Method In this…

Cardiac tissue engineering has emerged as a promising strategy to treat infarcted cardiac tissues by replacing the injured region with an ex vivo fabricated functional cardiac patch. Nevertheless, integration of the transplanted patch with the host tissue is still a burden, limiting its clinical application. Here, a bi-functional, 3D bio-printed cardiac patch (CP) design is proposed, composed of a cell-laden compartment at its core and an extracellular vesicle (EV)-laden compartment at its shell for better integration of the CP with the host tissue. Alginate-based bioink solutions were developed for each compartment and characterized rheologically, examined for printability and their effect…

Engineering hierarchical vasculatures is critical for creating implantable functional thick tissues. Current approaches focus on fabricating mesoscale vessels for implantation or hierarchical microvascular in vitro models, but a combined approach is yet to be achieved to create engineered tissue flaps. Here, millimetric vessel-like scaffolds and 3D bioprinted vascularized tissues interconnect, creating fully engineered hierarchical vascular constructs for implantation. Endothelial and support cells spontaneously form microvascular networks in bioprinted tissues using a human collagen bioink. Sacrificial molds are used to create polymeric vessel-like scaffolds and endothelial cells seeded in their lumen form native-like endothelia. Assembling endothelialized scaffolds within vascularizing hydrogels incites…