TY - THES A1 - Daus, Andreas T1 - Zellbasierte Biosensoren – Hybride Systeme aus dreidimensionalen in vitro Netzwerken und Mikroelektroden Arrays N2 - Mit der Entwicklung hybrider Strukturen aus Mikroelektroden Arrays und dreidimensionalen Sphäroiden wurde in dieser Arbeit ein funktionaler, deskriptiver Ansatz der Biosensorik adressiert. Während biochemische Sensoren ausschließlich analytische Informationen über die Wechselwirkung von Liganden und Rezeptoren liefern, erlauben zellbasierte Biosensoren eine physiologische Beschreibung biologischer Systeme in nativen bzw. chemisch oder physikalisch provozierten Zuständen. Dies impliziert für Anwendungen der Pharmakologie, Toxikologie und Grundlagenforschung hohes Potenzial, evoziert jedoch eine multidisziplinäre Aufgabe. Es werden zum einen in vitro Systeme benötigt, die den Ansprüchen eines physiologisch repräsentativen Abbilds eines Organismus genügen. Zum anderen sind technische Systeme erforderlich, die Zellreaktionen qualitativ und quantitativ verwertbar machen. KW - Array KW - Biosensor Y1 - 2013 ER - TY - CHAP A1 - Ritter, Sylvia A1 - Durante, Marco A1 - Helm, Alexander A1 - Steger, Frederik A1 - Daus, Andreas A1 - Frieß, Johannes T1 - Assessment of cardiotoxicity of heavy ions in vitro: generation and electrophysiology of cardiomyocytes T2 - 39th COSPAR Scientific Assembly, Mysore, India KW - Herzmuskelzelle KW - Kardiotoxizität Y1 - 2014 ER - TY - THES A1 - Bestel, Robert T1 - Simulation neuronaler Aktionspotentiale in Hinblick auf Zellform und Physiologie sowie deren Ableitung mittels extarzellulärer Mikroelektroden KW - Mikroelektrode KW - Nervenzelle Y1 - 2018 U6 - https://doi.org/10.18453/rosdok_id00002390 ER - TY - GEN A1 - Uhrig, Janis A1 - Emmerich, Florian T1 - Study on different template-based production processes for magnetic nanowires T2 - 22nd International Student Conference on Electrical Engineering POSTER 2018 N2 - Nickel-iron (NiFe) nanowires with a high contentof nickel and large aspect-ratio show promising characteris-tics for applications in modern micro-systems. In this study,nanowires with well-controlled diameter, height and compo-sition are fabricated using nanoporous poly-carbonate (PC)and anodized aluminum-oxide (AAO) membranes. Differ-ences between potentiostatic and pulsed deposition methodswere studied with regard to their flexibility and a recommen-dation for the best use of the individual types is given. Withthe application of the presented processes, future technolo-gies as magnetic energy-harvesting or nano-fluxgate sensorscan be improved. N2 - Poster KW - magnetic nanowires KW - MEMS KW - template-based KW - electroplating KW - Nanodraht Y1 - 2018 VL - 2018 IS - POSTER 2018 SP - 1 EP - 5 ER - TY - GEN A1 - Allig, Sebastian T1 - Controlled Cell Formation Using Bioprinting T2 - 22nd International Student Conference on Electrical Engineering POSTER 2018 N2 - Applying technologies of additive manufacturing to the field of tissue engineering created a pioneering new approach tomodelcomplex cell systemsartificially. Regarding its huge potential, bioprinting is still in its infancies and many questions are still unanswered. To address this issue, an extrusion-based bioprinting process was used to deposit human embryonic kidney (HEK) cellsin a defined pattern.It wasshownthat cells remained viable in the bioprinted construct for up to 8 days after printing (DAP). This work displays a proof of principle for a controlled cell formation which shall later be appliedtoin vitro drug screening tests. N2 - Poster KW - Bioprinting KW - Bioink KW - Tissue Engineering KW - In vitro cell systems KW - Biomaterial Y1 - 2018 VL - 2018 IS - POSTER 2018 SP - 1 EP - 5 ER - TY - GEN A1 - De Blasi, Stefano T1 - Simulation of Large Scale Neural Networks for Evaluation Applications T2 - 22nd International Student Conference on Electrical Engineering POSTER 2018 N2 - Understanding the complexity of biological neural networks like the human brain is one of the scientific challenges of our century. The organization of the brain can be described at different levels, ranging from small neural networks to entire brain regions. Existing methods for the description of functionally or effective connectivity are based on the analysis of relations between the activities of different neural units by detecting correlations or information flow. This is a crucial step in understanding neural disorders like Alzheimer’s disease and their causative factors. To evaluate these estimation methods, it is necessary to refer to a neural network with known connectivity, which is typically unknown for natural biological neural networks. Therefore, network simulations, also in silico, are available. In this work, the in silico simulation of large scale neural networks is established and the influence of different topologies on the generated patterns of neuronal signals is investigated. The goal is to develop standard evaluation methods for neurocomputational algorithms with a realistic large scale model to enable benchmarking and comparability of different studies. N2 - Poster KW - biological neural network KW - evaluation method KW - in silico KW - spike trains KW - Neuronales Netz Y1 - 2018 VL - 2018 IS - POSTER 2018 SP - 1 EP - 6 ER - TY - GEN A1 - Emmerich, Florian A1 - Ciba, Stefan T1 - Thin-film Micro-Heater for Fusion Bonding of Teflon-FEP Foils T2 - 21th International Student Conference on Electrical Engineering POSTER 2017 N2 - MEMS-based Micro-Heaters, in combination with thin-film temperature sensors, are often used for providing the necessary amount of thermal energy for sensor-applications. In this work, we propose an integrated micro-heater as actuator for fusion bonding of polymers, which can optimize the production process of electret-based micro-energy-harvesters. By adjusting the design parameters of thermoforming-molds, we can implement thin-film micro-heaters that are capable of generating temperatures of above 300°C for numerous cycles. Utilizing the integrated micro-heater allows local fusion bonding of Fluoroethylenepropylene (Teflon-FEP) foils on a micrometer-scale while reducing unnecessary thermal stress. This is beneficial for the longevity of the micro-energy-harvesters, while simultaneously improving its performance. N2 - Poster KW - Energy-Harvesting KW - Fusion Bonding KW - Micro-Heater KW - SU-8 KW - Teflon-FEP KW - Mikrosystemtechnik Y1 - 2017 VL - 2017 IS - POSTER 2017 SP - 1 EP - 5 ER - TY - JOUR A1 - Flachs, Dennis A1 - Ciba, Manuel T1 - Cell-based sensor chip for neurotoxicity measurements in drinking water JF - Lékař a technika - Clinician and Technology N2 - Our drinking water contains residues of pharmaceuticals. A sub-group of these contaminants are neuro-active substances, the antiepileptic carbamazepine being one of the most relevant. For assessment of the neurotoxicity of this drug at a sub-therapeutic level, a cell-based sensor chip platform has been realized and characterized. For this purpose, a microelectrode array chip was designed and processed in a clean room and optimized in terms of low processing costs and good recording properties. For characterization of the system neuronal cells were plated on microelectrode array chips and electrical activity was measured as a function of applied carbamazepine concentration. We found that the relative spike rate decreased with increasing drug concentration resulted in IC50 values of around 36 μM. This value is five orders of magnitude higher than the maximal dose found in drinking water. IC50 values for burst rate, burst duration and synchrony were slightly higher, suggesting spike rate being a more sensitive parameter to carbamazepine. KW - Microelectrode array KW - Carbamazepine KW - Neurotoxicity KW - Cell-based biosensor KW - Mikroelektrode KW - Array KW - Biosensor KW - Neurotoxizität Y1 - 2016 VL - 46 IS - 2 SP - 46 EP - 50 ER - TY - THES A1 - Frieß, Johannes T1 - Einfluss ionisierender Strahlung auf die elektrophysiologischen Eigenschaften kardialer Zellen N2 - Die zentrale Fragestellung der Strahlenbiologie behandelt die Wirkung von ionisierender Strahlung auf biologische Systeme. Zwar sind die bei Exposition mit ionisierender Strahlung entstehenden Gesundheitsrisiken bekannt, dennoch sind die Strahlungseffekte auf das Herz immer noch nicht sehr gut verstanden. Dabei ist die Exposition mit hohen Dosen ionisierender Strahlung ein anerkannter Risikofaktor in Bezug auf kardiovaskuläre Erkrankungen. KW - Elektrophysiologie KW - Herzmuskelzelle Y1 - 2016 ER - TY - GEN A1 - Kück, Nico-Wei T1 - In Vitro Platform for Acoustic and Electrophysiological Investigations of Ultrasound Neuromodulation N2 - The quality of life has increased dramatically over the past decades. Approximately one billion individuals worldwide will be aged 65 years or older by 2030. With the increasing age of human population, prevalence of neurodegenerative ailments, such as Parkinson’s disease or Alzheimer’s disease, increases. Brain pacemakers are proposed to treat their symptoms. They provide the electrical stimulation of neuronal regions of the central or peripheral nervous system. But for the implantation of brain pacemakers, surgery is needed. Those surgical interventions can be avoided by using transcranial stimulation methods such as Transcranial Magnetic Stimulation (TMS). However, magnetic fields lack the possibility of focusing. Ultrasound (US) offers transcranial characteristics as well and allows focusing on a specific target area in the brain. Over 60 years ago, the Hodgkin-Huxley (H-H) model was presented to simulate the electrophysiological activity of neurons but it lacks to describe the impact of mechanical soundwaves on action potentials in a neuron. N2 - Poster KW - In Vitro, Ultrasound, Neuromodulation, Neuron KW - Nervenstimulation KW - Ultraschall Y1 - 2017 ER -