3D Bioplotter Research Papers
A Percolation Model for Piezoresistivity in Conductor–Polymer Composites
Insulating polymer composites with conductive filler particles are attractive for sensor applications due to their large piezoresistive response. Composite samples composed of a polymer matrix filled with particles of doped semiconductor that gives a piezoresistive response that is 105 times larger than that of bulk semiconductor sensors are prepared here. The piezoresistance of such composite materials is typically described by using a tunneling mechanism. However, it is found that a percolation description not only fits prior data better but provides a much simpler physical mechanism for the more flexible and soft polymer composite prepared and tested in this study. A…
Bioprinting of an osteocyte network for biomimetic mineralization
Osteocytes, essential regulators of bone homeostasis, are embedded in the mineralized bone matrix. Given the spatial arrangement of osteocytes, bioprinting represents an ideal method to biofabricate a 3D osteocyte network with a suitable surrounding matrix similar to native bone tissue. Here, we reported a 3D bioprinted osteocyte-laden hydrogel for biomimetic mineralization in vitro with exceptional shape fidelity, a high cell density (107 cells per ml) and high cell viability (85–90%). The bioinks were composed of biomimetic modified biopolymers, namely, gelatine methacrylamide (GelMA) and hyaluronic acid methacrylate (HAMA), with or without type I collagen. The osteocyte-laden constructs were printed and cultured…
3D extruded composite thermoelectric threads for flexible energy harvesting
Whereas the rigid nature of standard thermoelectrics limits their use, flexible thermoelectric platforms can find much broader applications, for example, in low-power, wearable energy harvesting for internet-of-things applications. Here we realize continuous, flexible thermoelectric threads via a rapid extrusion of 3D-printable composite inks (Bi2Te3 n- or p-type micrograins within a non-conducting polymer as a binder) followed by compression through a roller-pair, and we demonstrate their applications in flexible, low-power energy harvesting. The thermoelectric power factors of these threads are enhanced up to 7 orders-of-magnitude after lateral compression, principally due to improved conductivity resulting from reduced void volume fraction and partial…