Kolloquiumsvortrag: "Multi User MEMS environment to test microorganisms in aqueous media"
Institut für Materialwissenschaft, Kaiser Str. 2, Geb.C , Raum "Aquarium"
Multi User MEMS environment to test microorganisms in aqueous media
Dr. Stephan Warnat/ Dalhousie University, Halifax, Canada
90 % of international traded products are transported using marine transportation. Transport and delivery of microorganisms through ballast water from departure to arrival location is an unwanted consequence. Some organisms are invaders or alien species and change the marine ecosystem irreversibly. These irreversible changes cause annual damage in ecosystems, farming and tourism of several million dollars.
I will present our current work on a cell monitoring system using Micro-Electrochemical Systems (MEMS) in a microfluidic camera environment: 1) Devices have to work reliable in seawater. Several MEMS materials show immediate corrosion during operation in seawater. An encapsulation strategy of active structures using Al2O3, TiO2 multilayers deposited by Atomic Layer Deposition (ALD) will be presented which allowed a constant operation in seawater for 30 days; 2) A novel Gecko inspired adhesive technology is currently evaluated to form sealed fluidic chamber systems on top of the MEMS. This technology allows fluidic sealing without bonding processes; 3) The mechanical stiffness of single cells allow an assessment of cell viability. An approach was developed to measure the mechanical cell stiffness based on differential displacement measurements on a two stage spring system. Displacements were measured optically within a ±10 nm accuracy during MEMS operation in aqueous media. This technique allowed differentiation of viable and non-viable Saccharomyces cerevisiae (baker’s yeast). I will conclude the talk with our plans to integrate the developed MEMS platform into a mobile camera platform.