Integrated Micro-Optics for Microfluidic Systems

Microfluidic systems have a large variety of applications in biomedicine and life sciences. One of the problems occurring in practical systems is the adhesion of cells and micro-particles to the walls of microfluidic channels and reservoirs. For scientific examinations, e.g. for drug testing, it is necessary to expose specific test cells to different media. The cells are moved between the reservoirs e.g. by optical tweezers and kept there for a specific period of time [1,2]. This is a very time consuming experiment if the cell under examination must be kept in the laser trap during the whole reaction cycle. Introducing an array of fixed traps in the reservoir keeping a few cells, each in its own trap, would make total control of the experiment possible. In this case the movable optical trap is required only for transport from one reservoir to another. In this project we investigate possibilities to integrate optical functionality in the microfluidic system to generate the static weak optical traps without additional optical components which would have to be aligned to the microfluidic system. Alternatively this system setup could be used to generate light distributions for sorting particles within a flow [3].