Scientists of Karlsruhe Institute of Technology (KIT) have developed a new process to structure surfaces and to apply or detach functional molecules. They use UV light for the formation or breaking of so-called disulfide bridges, i.e. bonds of sulfur atoms. Both photodynamic reactions allow for a temporally and spatially controlled and reversible modification of the surface and, hence, can be used to produce functional interfaces. The process is reported in the journal Angewandte Chemie.