Existing methods for the isolation of DNA are expensive and elaborate and fail with DNA from difficult samples. Examples for difficult samples are fat containing food, soil samples or dried body fluids. DNA purified with established methods from such samples is unstable and can not be used in following amplifications or analysis.In order to develop novel methods for DNA purification from difficult samples we test new solid phases for the absorption of DNA damaging compounds. The new methods will be miniaturised and adapted to existing high-throughput systems.