TY - JOUR A1 - Schlegel, Volker A1 - Engels, Andreas A1 - Stoycheva, Vesela A1 - Bifaretti, Stefano A1 - Foitzik, Andreas T1 - From Biomaterial to Organoid - Bioprinting for Practice JF - Materials Science Forum N2 - The current state of technology for 3D printing with biomaterials is based on the extrusion of viscous materials. Mostly, extrusion heads utilize pneumatic pressure systems or stepper motors to force the substrate onto a surface. These methods are well developed for high viscouse materials. However, processing low viscous liquids may cause leakages in the system. This could be solved by applying continuous extrusion. Additionally, in order to process gelable substrates, such as gelatine and agar, tempered print heads in combination with a multi stage tempering system are required to prevent the system from clogging. The ongoing work presented in this paper focuses on the development of an extrusion system, which should be able to process multiple viscosities of gelatine sequentially. In order to achieve this, several measurements to examine the properties, as well as the material parameters of different biomaterials are performed. In this process gel point, force resistance and elasticity are the factors of particularly interest. Due to their ability to gel and their availability, the most relevant biomaterials are gelatine and agar. Using this data, an extrusion system involving a peristaltic pump, a heated tube and a nozzle, has been developed. The next step envisaged is to calibrate the extruder based on the obtained data and finally to validate the printing process by printing simple geometric structures. Assuming that a positive evaluation is obtained, the printing system will be tested for printing first organic test structures from patient data using the examined biomaterials. KW - agar KW - biomaterial KW - bioprinting KW - gelatin KW - validation of material parameters Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:526-opus4-18802 SN - 0255-5476 SN - 1662-9752 VL - 1016 SP - 1285 EP - 1290 PB - Trans Tech Publications ER - TY - JOUR A1 - Engels, Andreas A1 - Schlegel, Volker A1 - Jacobs, Hannes A1 - Großelindemann, Niklas A1 - Morshed, Md. Niaz A1 - Stenglein, Antonia Sigrid A1 - Bonaiuto, Vincenzo A1 - Foitzik, Andreas T1 - 3d Printer Heads for Extrusion of Biologicals Gels JF - Materials Science Forum N2 - Processing biological materials with 3-dimensional (3D) printers has attracted increasing interest in several research areas. At the same time, off-the-shelf solutions are increasingly available in a wider variety to meet the current market demand. However, most of the available bioprinters are closed source, thus, modifications are quite challenging or require an avoidable consultation process with the manufacturer. Furthermore, the entry prices for basic machines amount to several thousands of euros. Whereas, high-end 3D bio printers with a vast array of features are available for several hundred thousand euros. Due to the immense potential of this tool in the field of biotechnology it is important to extend the availability of this technology for research purposes in terms of adaptability and price. This ongoing work focuses on open-source 3D printer heads with the ability to extrude biological materials. The print heads include several techniques to process low as well as high viscose biomaterials such as agar and gelatin. Additionally, obstacles such as continuous substrate tempering or integration into existing 3D printers are addressed. The work presented is open source and thus freely adaptable to any user’s specific needs. Our goal is to process a diverse range of biomaterials with different print techniques. KW - biofabrication KW - bioprinting KW - Open Source KW - process parameter improvement Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:526-opus4-18773 SN - 0255-5476 SN - 1662-9752 VL - 1016 SP - 435 EP - 439 PB - Trans Tech Publications ER - TY - JOUR A1 - Böhme, Andrea A1 - Nemak, Detlef A1 - Lietzau, Kai-Henning A1 - Wolf, Eckart A1 - Foitzik, Andreas T1 - Adaption of 3D Printing for Rapid Tooling JF - Materials Science Forum N2 - Over the course of the last decade 3D printing has become a more established technology in terms of prototype development (rapid prototyping). The current effort is focused on transferring this knowhow into a product driven approach in order to manufacture even small batch sizes more economic. In terms of this work, this idea is adapted for the development of injection molds (rapid manufacturing). Hereby, a hardened polymer is used to create a forming cavity instead of tool-steel. In order to fulfil the mechanical process requirements of micro injection molding such as form stability under temperature and pressure this cavity is nevertheless integrated into a metal housing. A first set of experiments has been carried out using this develop mold to verify the capabilities of the developed prototype as well as molding process. Based on these first results, an optimization is carried out to improve the next iteration of this molding tool. KW - CAD/CAM KW - mold KW - parametrization KW - rapid manufacturing KW - rapid tooling Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:526-opus4-18784 SN - 0255-5476 SN - 1662-9752 VL - 1016 SP - 280 EP - 285 PB - Trans Tech Publications ER - TY - JOUR A1 - Schlegel, Susanne A1 - Krumnow, Erik A1 - Böhme, Andrea A1 - Minieri, Marilena A1 - Foitzik, Andreas T1 - Miniaturized Blood Sampling System with Integrated Sample Preparation JF - Materials Science Forum N2 - Blood sampling as well as sample preparation are time consuming and requires a strict procedure, which is generally performed by medical trained personal. Not carrying out the procedure correctly could result in an infection of the patient or contamination of the sample itself. These limitations should be especially considered in case of pandemic outbreaks. In order to handle such a high number of patients a novel sample preparation system paired with modern blood sampling procedure is necessary. For this reason, a new device for blood sampling and preparation is designed containing an integrated microfluidic system. The fabrication is carried out by utilizing micro moulding of PDMS as well as micro milling. A first set of initial experiments as part of a first-generation study shows promising results. However, further steps of optimisation considering flow time and preparation cycle are part of a second-generation study. KW - mechanical system KW - polymer material KW - sample preparation Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:526-opus4-18812 SN - 0255-5476 SN - 1662-9752 VL - 1016 SP - 1280 EP - 1284 PB - Trans Tech Publications ER -