In this issue, C. L. Evans et al. review oxygen sensing methods in biomedicine on a range of scales: How can the physiological distribution and real-time dynamics of oxygen from subcellular to macroscopic levels be quantified? The Highlights deal with programmable supramolecular polymerizations (E. W. Meijer) and the mechanism of carbon monoxide dehydrogenase (M. W. Ribbe). In her Editorial, V. W.-W. Yam discusses the field of inorganic chemistry.

In the Communications section, J. M. Kelly et al. describe how the reversal of a single base-pair step controls guanine photooxidation (see picture). T. E. Nielsen et al. present a four-component reaction for the synthesis of dioxadiazaborocines, and M. Zhu et al. succeeded in assembling a Au₆₀ nanocluster with five Au₁₃ building blocks.

• Angewandte Chemie 29/2015: Sensing Chemistry,
  Angew. Chem. Int. Ed. 2015, 54 (29).