ABSTRACT
Introduction Coumarins, or benzo-α-pyrones, are a very large and important family of compounds. eir dening structure consists of fused pyrone and benzene rings, with the pyrone carbonyl group at position 2 [1]; this structure is illustrated in Figure 1 for the coumarin parent molecule (IUPAC name: 2H-chromen-2-one, and also known as 1-benzopyran-2-one). Coumarins are widely occurring in nature, with coumarin itself rst isolated in 1820 from a specic variety of bean, and many other coumarin derivatives found in a wide range of plants [1]. As a group, coumarins exhibit interesting uorescence properties, which include a high degree of sensitivity to their local environment, including polarity and viscosity. is sensitivity has led to their widespread application as sensitive uorescent probes of a wide range of systems, including homogeneous solvents and mixtures, and heterogeneous materials; the latter is the focus of this article. Specically, the purpose of this review is two-fold: 1) to provide a detailed review of the use of coumarin uorescence to probe the nature and properties of heterogeneous materials and systems, and 2) to provide a guide to current and future researchers studying heterogeneous and supramolecular systems to the utility of and information provided by coumarins as uorescent probes.
