The fabrication and modeling of a microorganism separation stage for oceanographic investigations based on MEMS-grippers is targeted in this project. The microorganism viability must be guaranteed. The thermal, electrical and mechanical impact on microorganisms is investigated.

• Applicant: Professor Dr.-Ing. Stephan Warnat
• Subject Area: Microsystems
• Term: from 2012 to 2014
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 207342776

The characterization of separated microorganisms plays a major role to understand several oceanographic phenomenas. The CO2 buffering is just one example. Microorganisms must be separated from microbial communities to obtain a pure signal of the organism of interest. Some experimental separation approaches are currently in use. However, these techniques use expensive assemblies and well trained personal is often necessary to operate these instruments. Microsystem-Technologies (MEMS) allow the fabrication of microgrippers. The separation of migroorganism by using MEMS microgrippers is principally shown in the literature. However, the viability of oceanographic microorgansim is not investigated yet when they are separated by MEMS-microgrippers. Thermal and electrical interaction phenomena between the gripper and the organism can be a critical aspect. The actuating MEMS structures of microgrippers are based on thermal expansion of the structures or by electrostatic attraction. The arising temperatures or electrical potentials are critical for organisms. Theoretical calculations and finite element simulations will show how the MEMS fabrication technologies allow a thermal and electrical decoupling of the actuating structures from the organisms. The Multi-User MEMS fabrication process will be taken as an example. The optimized microgrippers structures will be fabricated afterwards and the microorganism viability will be tested. The growth behaviour after separation by using the MEMS microgripper will be investigated. Seawater can be viewed as a critical medium for the device reliability due to the high salinity. Thus, reliability tests of MEMS structures in seawater will be also investigated in this project.

• DFG Programme: Research Fellowships
• International Connection: Canada
• Host: Professor Dr. Ted Hubbard