Integrated Micro-Optics for Microfluidic Systems

Within the field of biomedicine and life science microfluidic systems gain importance for a variety of applications. For testing the reaction of cells and bacteria to different chemicals it is possible to use optical tweezers for moving them between different reservoirs. However, when leaving the cells untrapped in the reservoirs they often adhere to the channel bottom and cannot be removed without damage. Keeping the objects in the trap for the whole experiment would be very time consuming. As an approach for making these experiments more efficient integrated microoptical elements can be used for generating a specific light distribution e.g. a set of focal points in the reservoirs. Within these foci the particles will be kept away from the walls of the reservoirs so that they can be removed easily. We present the concept, systems design as well as first experiments to evaluate the potential of this approach.