@article{EngelsZinnBonaiutoetal.2018, author = {Engels, Andreas and Zinn, Steffen and Bonaiuto, Vincenzo and Foitzik, Andreas}, title = {Improved Syringe Extruder for Improved Processing of Biological Materials}, series = {Materials Science Forum}, volume = {941}, journal = {Materials Science Forum}, publisher = {Trans Tech Publications}, issn = {0255-5476}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:526-opus4-18701}, pages = {2442 -- 2447}, year = {2018}, abstract = {3 dimensional (3D) printing evolved during the last decade to a consumer friendly and affordable craft. Furthermore, implementations of this techniques in the field of biotechnological research and development within laboratories is a very expansive process. Bio-printers' prices cover a wide spectrum and most basic models are available for around 5000€. On the other end, high-end printer machines with a vast variety of features are available for several hundreds of thousands of euros. Thus, due to the immense potential in the field of Biotechnology the availability of this technology for research purpose should be enhanced. A developed ecological syringe extruder prototype for processing of biological based gels has been further improved. The original prototype was capable to processing multiple layers of agar with concentrations of 1\% and 2.5\%. Based on these results the prototype was revised regarding printing process parameter, which include among others applied forces to the substrate, air-ventilation, and heating of the substrate. The process behavior will be simulated with computational fluid dynamics for the processing of biological based substrate. After a concluding validation these results are intended to be implemented into a new design for improved processing of a variety of bioinks.}, language = {en} } @article{SchlegelEngelsStoychevaetal.2021, author = {Schlegel, Volker and Engels, Andreas and Stoycheva, Vesela and Bifaretti, Stefano and Foitzik, Andreas}, title = {From Biomaterial to Organoid - Bioprinting for Practice}, series = {Materials Science Forum}, volume = {1016}, journal = {Materials Science Forum}, publisher = {Trans Tech Publications}, issn = {0255-5476}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:526-opus4-18802}, pages = {1285 -- 1290}, year = {2021}, abstract = {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.}, language = {en} } @article{SchlegelEngelsBifarettietal.2018, author = {Schlegel, Volker and Engels, Andreas and Bifaretti, Stefano and Foitzik, Andreas}, title = {Validation of Material Parameters of Collagen Compositions for the Application as a Bioink}, series = {Materials Science Forum}, volume = {941}, journal = {Materials Science Forum}, publisher = {Trans Tech Publications}, issn = {0255-5476}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:526-opus4-18764}, pages = {2437 -- 2441}, year = {2018}, abstract = {The novel approach of an individualized medicine affects nowadays various areas of therapeutic treatment. Primarily, these include the application of pharmaceuticals, private point-of-care solutions, surgical procedures as well as steps of rehabilitation. However, beside these existing strategies the development of patient specific models for the training of clinical personal is currently insufficient. Such models are essential to prepare a personalized approach of medical care. One possible solution to address this problem could be the adaption of the established 3d printing technology for the processing of suitable biopolymers. The presented work is focused on the development of a printing system utilizing collagen. Therefore, it is intended to design multiple extrusion heads in accordance with the material parameters. In order to achieve the aspired physiological properties of the final model, a first set of experiments will be performed with several compositions of collagen to validate the fundamental mechanical characteristics. Hereby, the elasticity, thermal stability, force resistance as well as the haptic behaviour are of most interest. Afterwards, these obtained experimental results should be used to simulate the extrusion process and to validate the extruder concepts. In case of a positive evaluation these concepts are realized by using rapid prototyping technologies. Finally, this novel 3d printer will be used to print first organic test structures with collagen.}, language = {en} } @article{EngelsSchlegelJacobsetal.2021, author = {Engels, Andreas and Schlegel, Volker and Jacobs, Hannes and Großelindemann, Niklas and Morshed, Md. Niaz and Stenglein, Antonia Sigrid and Bonaiuto, Vincenzo and Foitzik, Andreas}, title = {3d Printer Heads for Extrusion of Biologicals Gels}, series = {Materials Science Forum}, volume = {1016}, journal = {Materials Science Forum}, publisher = {Trans Tech Publications}, issn = {0255-5476}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:526-opus4-18773}, pages = {435 -- 439}, year = {2021}, abstract = {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.}, language = {en} } @inproceedings{HauschultzFriedoJacobsetal.2022, author = {Hauschultz, Mike Thomas and Friedo, Maria Helene and Jacobs, Hannes and Lafta, Mohammad and Engels, Andreas and Foitzik, Andreas}, title = {Low-cost Pipettierroboter auf Basis einer Portalfr{\"a}se}, series = {Open Conference Proceedings}, volume = {2}, booktitle = {Open Conference Proceedings}, publisher = {TIB Open Publishing}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:526-opus4-17649}, pages = {187 -- 191}, year = {2022}, abstract = {Zur Herstellung von langfristig stabilen Metall-Kautschuk-Verbunden sind chemische Haftvermittler notwendig. Nach Auftrag dieser wird Kautschuk mittels Gummispritzgießen auf die metallischen Grundk{\"o}rper aufgebracht. In Klein- und Kleinstserien kann der Haftvermittler in pr{\"a}zisen Volumina h{\"a}ndisch mit Hilfe eines Fluid-Dispensers aufgetragen werden. Allerdings verhindert dies eine Homogenit{\"a}t und Gleichheit der Schichtdicke, wodurch die Zuverl{\"a}ssigkeit und St{\"a}rke der Haftung variieren k{\"o}nnen. Als technische L{\"o}sung wurde ein Pipettierroboter avisiert. Mit Hilfe mehrerer mechanischer und elektrischer Adaptionen - so auch einer neuen Steuerungstechnik - wurden verschiedene Fluid-Dispenser auf 3-Achs-Portalfr{\"a}sen integriert. Somit konnte die volle Funktionsf{\"a}higkeit erreicht werden.}, language = {de} } @inproceedings{FriedoHauschultzJacobsetal.2022, author = {Friedo, Maria Helene and Hauschultz, Mike Thomas and Jacobs, Hannes and Lafta, Mohammad and Engels, Andreas and Foitzik, Andreas}, title = {Steuerungstechnik f{\"u}r das Auftragen von fluiden Haftvermittlern}, series = {Open Conference Proceedings}, volume = {2}, booktitle = {Open Conference Proceedings}, publisher = {TIB Open Publishing}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:526-opus4-17670}, pages = {217 -- 219}, year = {2022}, abstract = {The goal of this project was to enable an automated solution for the application of bonding agents to metallic bodies in the nanoliter range. For the automated application of adhesion promoters, a new control unit based on a mainboard for controlling 3D printers was used, with Marlin serving as the firmware. Adaptations were necessary in the area of motor currents, speeds, acceleration, sensitivity, print bed size and selection of mainboard and display. For the traverse paths, G-code was generated using a program in Python. For homogeneous and uniform wetting, the individual objects to be wetted are approached and the pipetting process is controlled. It was possible to establish the complete functionality.}, language = {de} } @article{GottschalkStollfussLietzauetal.2017, author = {Gottschalk, Josefine Johanna and Stollfuß, Carsten and Lietzau, Kai-Henning and Foitzik, Andreas and Richetta, Maria}, title = {Conceptual study for long-term monitoring of chemotherapeutic induced cell reactions by ESPI}, series = {tm - Technisches Messen}, volume = {85}, journal = {tm - Technisches Messen}, number = {2}, issn = {2196-7113}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:526-opus4-10676}, pages = {111 -- 118}, year = {2017}, abstract = {During the last years, various approaches on an individualized drug therapy for benign cells have been researched. However, due to the complex topic a universal approach has not been found up until this point. Commonly, the effect of cytotoxic drugs on benign cells is in most cases the same compared to regular cells while the actual effect on patient still can't be predicted. In order to reduce unwanted side effects or unspecific drug reactions a test system for patients which allows to analyse the interaction between cytotoxic agents and the targeted cells is needed. Furthermore, this should also include an adequate measurement system which is capable to work in a natural environment and without any additional preparation. In terms of this work, a first proof of concept with different benign cells and cytotoxic agents is presented while monitoring the obtained displacement using electronic speckle pattern interferometry (ESPI).}, language = {en} } @article{BoehmeNemakLietzauetal.2021, author = {B{\"o}hme, Andrea and Nemak, Detlef and Lietzau, Kai-Henning and Wolf, Eckart and Foitzik, Andreas}, title = {Adaption of 3D Printing for Rapid Tooling}, series = {Materials Science Forum}, volume = {1016}, journal = {Materials Science Forum}, publisher = {Trans Tech Publications}, issn = {0255-5476}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:526-opus4-18784}, pages = {280 -- 285}, year = {2021}, abstract = {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.}, language = {en} } @article{SchlegelKrumnowBoehmeetal.2021, author = {Schlegel, Susanne and Krumnow, Erik and B{\"o}hme, Andrea and Minieri, Marilena and Foitzik, Andreas}, title = {Miniaturized Blood Sampling System with Integrated Sample Preparation}, series = {Materials Science Forum}, volume = {1016}, journal = {Materials Science Forum}, publisher = {Trans Tech Publications}, issn = {0255-5476}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:526-opus4-18812}, pages = {1280 -- 1284}, year = {2021}, abstract = {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.}, language = {en} } @article{SchattschneiderPiontekJacobsetal.2024, author = {Schattschneider, Christoph and Piontek, Sina and Jacobs, Hannes and B{\"o}hme, Andrea and Sirena, Concetta and Foitzik, Andreas}, title = {Proof of Principle of Wastewater Treatment using Plasma Discharge to Reduce the Amount of Methylparaben}, series = {Athens Journal of Sciences}, volume = {11}, journal = {Athens Journal of Sciences}, number = {1}, publisher = {Athens Institute for Education and Research}, issn = {2241-8466}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:526-opus4-18649}, pages = {29 -- 38}, year = {2024}, abstract = {Synthetic substances like many pharmaceuticals, preservatives or other chemical compounds are actually very difficult to handle in sewage treatment. These compounds are very stable in aqueous solution and their degradation reactions are insufficient. Therefore, to eliminate these substances from wastewater additional afford is necessary. Extreme conditions like pH value, redox potential, chemical or physical energy need to be present. With our study we try to show that the use of plasma discharge could be a solution to this problem. Using the example of methylparaben, a preservative, we could show, that the physical energy of plasma discharge is able to initialize the degradation reaction in aqueous environment. The concentration was reduced by up to 70 percent in our setting depending on the treatment duration. Overall, the system showed potential to optimize wastewater treatment. Further examinations are necessary for example regarding undesirable by-products.}, language = {en} }