3D Bioplotter Research Papers

Three-dimensional (3D)-printed constructs made of polycaprolactone (PCL) and chondrocyte-impregnated alginate hydrogel (hybrid cartilage constructs) mimic the biphasic nature of articular cartilage, offering promise for cartilage tissue engineering (CTE) applications. However, the regulatory pathway for medical device development requires validation of such constructs through in vitro bench tests and in vivo preclinical examinations premarket approval. Furthermore, non-invasive imaging techniques are required for effective evaluation of the progress of these cartilage constructs, especially when implanted in animal models or human subjects. However, characterization of the individual components of the hybrid cartilage constructs and their associated time-dependent structural changes by currently available non-invasive…

In tissue engineering, non-invasive imaging of biomaterial scaffolds and tissues in living systems is essential to longitudinal animal studies for assessments without interrupting the repair process. Conventional X-ray imaging is inadequate for use in soft tissue engineering due to the limited absorption difference between the soft tissue and biomaterial scaffolds. X-ray phase-based imaging techniques that derive contrast from refraction or phase effects rather than absorption can provide the necessary contrast to see low-density biomaterial scaffolds and tissues in large living systems. This paper explores and compares three synchrotron phase-based X-ray imaging techniques—computed tomography (CT)-diffraction enhanced imaging (DEI), -analyzer based imaging…

Synchrotron radiation inline phase-contrast imaging combined with computed tomography (SR-inline-PCI-CT) offers great potential for non-invasive characterization and three-dimensional visualization of fine features in weakly absorbing materials and tissues. For cartilage tissue engineering, the biomaterials and any associated cartilage extracellular matrix (ECM) that is secreted over time are difficult to image using conventional absorption-based imaging techniques. For example, three-dimensional printed polycaprolactone (PCL)/alginate/cell hybrid constructs have low, but different, refractive indices and thicknesses. This paper presents a study on the optimization and utilization of inline-PCI-CT for visualizing the components of three-dimensional printed PCL/alginate/cell hybrid constructs for cartilage tissue engineering. First, histological analysis…

Three-dimensional (3D) bioprinting of hybrid constructs is a promising biofabrication method for cartilage tissue engineering because a synthetic polymer framework and cell-impregnated hydrogel provide structural and biological features of cartilage, respectively. During bioprinting, impregnated cells may be subjected to high temperatures (caused by the adjacent melted polymer) and process-induced mechanical forces, potentially compromising cell function. This study addresses these biofabrication issues, evaluating the heat distribution of printed polycaprolactone (PCL) strands and the rheological property and structural stability of alginate hydrogels at various temperatures and concentrations. The biocompatibility of parameters from these studies was tested by culturing 3D hybrid constructs bioprinted…

Long-term in vivo studies on animal models and advances from animal to human studies should rely on noninvasive monitoring methods. Synchrotron radiation (SR)-diffraction enhanced imaging (DEI) has shown great promise as a noninvasive method for visualizing native and/or engineered tissues and bio-microstructures with appreciable details in situ. The objective of this study was to investigate SR-DEI for in situ visualization and characterization of tissue-engineered scaffolds implanted in cartilage. A piglet stifle joint implanted with an engineered scaffold made from poly-ɛ-caprolactone was imaged using SR computed tomography (CT)-DEI at an X-ray energy of 40 keV. For comparison, in situ visualization was also…