The starting point for this thesis was the idea to use magnetic markers for the manipulation of biomolecules directly on-chip. The magnetic fields that are needed for the manipulation can be created by currents through conducting lines on a Si-wafer. Together with magnetoresistive sensors, everything that is needed for a magnetic biosensor can be integrated into a small chip using standard methods of micro-electronics. Besides several advantages, such as low cost and portability, this setup opens up many possibilities for new measurements in the micro and nano cosmos.
This chapter provides all information about the basic setup of all samples and discusses several problems that have to be considered. Besides the first simple approach, several examples for manipulations on a chip will be presented and discussed.