3D Bioplotter Research Papers

In vitro models of soft tissues, such as neural, vitreous, or hematopoietic human tissues, require three-dimensional (3D), soft, and functionalized constructs that mimic the complex extracellular microenvironment and support tissue growth and differentiation. While bioprinting has gained significant interest in bioengineering, there is limited research on process control for the biomanufacturing of soft tissues, which is still in its early stages. Material extrusion of suspended hydrogels has shown promise in processing low-viscosity inks, but challenges in developing bioinks that maintain good shape fidelity, repeatability, and long-term stability in culture media have slowly progressed. In this study, we optimize the bioprinting…

The fabrication of three-dimensional (3D) bioprinted free-standing, low viscous, cell-laden hydrogels with good resolution, low cytotoxicity, and mechanical properties, comparable to native soft tissues, is a current challenge in tissue engineering. Recently, a new syringe extrusion approach, called Freeform Reversible Embedding of Suspended Hydrogels (FRESH), has been introduced to enhance 3D-bioprinting of soft hydrogels. Printing is conducted with the material embedded in a thermo-reversible gelatin bath, which acts as supporting material and can also initiate in-situ crosslinking when proper crosslinker agents are added. This work is the first to develop a 3D FRESH printable, low-cost, polymeric hydrogel composed of sodium…

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…