3D bioprinting, a paradigm shift in tissue engineering holds a promising perspective for regenerative medicine and disease modelling. 3D scaffolds are fabricated for subsequent cell seeding or incorporated directly to the bioink to create cell-laden 3D constructs. A plethora of factors relating to bioink properties, printing parameters and post print curing play a significant role in the optimisation of the printing process. Although qualitative evaluation of printability has been investigated largely, there is a paucity of studies on quantitative approaches to assess printability. Hence, this study explores machine learning as a novel tool to evaluate printability quantitatively and to fast…
Wounds impact millions of patients every year and represent a serious cause of morbidity and mortality worldwide, yet current treatment outcomes are far from ideal. Therapies based on delivery of multiple growth factors offer a promising approach for optimal wound management; however, their high production cost, low stability, and lack of effective delivery system limits their application in the clinic. Platelet lysate is a suitable, abundant and cost-effective source of growth factors that play an important role in the healing cascade. The aim of this current work is to develop an extrusion-based bioink consisting of platelet lysate (PL) and gelatin…
3D bioprinting has been increasingly employed in skin tissue engineering for manufacturing living constructs with three-dimensional spatial precision and controlled architecture. There is however, a bottleneck in the tunability of bioinks to address specific biocompatibility challenges, functional traits and printability. Here we report on a traditional gelatin methacryloyl (GelMA) based bioink, tuned by addition of an ulvan type polysaccharide, isolated from a cultivated source of a specific Australian Ulvacean macroalgae (Ul84). Ul84 is a sulfate- and rhamnose-rich polysaccharide, resembling mammalian glycosaminoglycans that are involved in wound healing and tissue matrix structure and function. Printable bioinks were developed by addition of…
As scaffolds approach dimensions that are of clinical relevance, mechanical integrity and distribution becomes an important factor to the overall success of the implant. Hydrogels often lack the structural integrity and mechanical properties for use in vivo or handling. The inclusion of a structural support during the printing process, referred to as hybrid printing, allows the implant to retain structure and protect cells during maturation without needing to compromise its biological performance. In this study, scaffolds for the purpose of auricular cartilage reconstruction were evaluated via a hybrid printing approach using methacrylated Gelatin (GelMA) and Hyaluronic acid (HAMA) as the…
In the present work we have revisited the application of quantitative ultrasound imaging (QUI) to cellular hydrogels, by using the reference phantom method (RPM) in combination with a local attenuation compensation algorithm. The investigated biological samples consisted of cell-laden collagen hydrogels with PC12 neural cells. These cell-laden hydrogels were used to calibrate the integrated backscattering coefficient (IBC) as a function of cell density, which was then used to generate parametric images of local cell density. The image resolution used for QUI and its impact on the relative IBC error was also investigated. Another important contribution of our work was the…
Articular cartilage injuries experienced at an early age can lead to the development of osteoarthritis later in life. In situ 3D printing is an exciting and innovative bio-fabrication technology that enables the surgeon to deliver tissue- engineering techniques at the time and location of need. We have created a hand- held 3D printing device (Biopen) that allows the simultaneous co-axial extrusion of bioscaffold and cultured cells directly into the cartilage defect in vivo in a single session surgery. This pilot study assesses the ability of the Biopen to repair a full thickness chondral defect and the early outcomes in cartilage…