Biologic systems such as microorganisms produce various types of particles. In our sense particles are either solids such as nanoparticles and diatom shells (frustules) or macromolecules such as proteins and polysaccharides and bio polymers. On the one hand we investigate particle production under controlled cultivation conditions by means of heterotrophic and photoautotroph microorganisms. On the other hand we aim for their purification. Our main techniques for the refinement of macromolecules base on electric an magnetic forces. We are developing innovative downstream processes such as pressure electro filtration and magnetic separation.