The investigation of small-scale flow structures and near-wall boundary layer phenomena in turbulent reactive as well as non-reactive flows attracts increasing interest in the fields of fluid dynamics and combustion research. The understanding of heat and species transport close to walls is important for many combustion applications. In recent years a number of techniques using different molecular tracers have been developed for non-intrusive investigations of flow structures1-4. In the study presented herein, a new flow tagging technique based on photolytically generated NO5 was used. Air flows with geometric Reynolds-numbers ranging from 6.000 to 24.000 were seeded with NO2 at concentrations in the order of few hundreds of ppm. A NO-structure was generated by photodissociation and imaged by laser-induced fluorescence (LIF) at different delays after its formation.