Controllable membrane system

• Applicants: Professor Dr.-Ing. Andreas Richter; Professor Dr.-Ing. Thomas Wallmersperger
• Subject Area: Microsystems ; Biological Process Engineering ; Polymer Materials
• Term: since 2017
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 382900294

The problem of the controllable membrane system is highly topical and relevant for the study of (biological) fluids, as could be seen in particular in the point-of-care tests in the Corona pandemic. After developing a controllable membrane system for the investigation of biological fluids in the first phase of the project, the focus is now on hydrogel-based microfluidic platforms. The control of these platforms can be chemofluidic or microelectromechanical. In the proposed second phase of the project, the smart material concept will focus on chemofluidic integrated circuits that perform control functions over chemical and physical variables. Specifically, ring muscle-inspired sphincter valves will be developed that exhibit outstanding properties, for example, due to (i) the smallest possible dead volume, (ii) very large open/close ratios, or (iii) their size scalability. Thus, these valves have a high potential for multiple functionalities for nanoscale and microscale systems, which are currently not realizable. In order to provide a design and technological basis for the hydrogel-based valve concept, modeling and simulation of the valve's behavior will be carried out at the Institute of Solid Mechanics. A modeling methodology will be developed that realizes the fluid-structure interaction as well as the multiphase material character of the hydrogels. Numerical simulations using the finite element method will investigate the resilience and reliability of the system to disturbance variables. The Institute of Semiconductors and Microsystems will create manufacturing and integration concepts as well as the constructive basis for sphincter valves. In particular, the size-scalable production of these valves will be enabled, which can then be integrated into microrobot bodies. After successful realization of both the fabrication and the numerical model, application-oriented investigations will be carried out. Sphincter valves will be applied in microrobotic structures to control the dynamics of drug release. Numerical investigations will show the influence of the system parameters, such as the stimulus or fluid pressures, on the valve system. If such systems are successfully implemented, novel microrobotic systems with integrated valve technology can be used for medication or biopsies in the future.

• DFG Programme: Research Grants
• Co-Investigator: Professor Dr. Jochen Hampe