A Spiropyran-Based Ensemble for Visual Recognition and Quantification of Cysteine and Homocysteine at Physiological Levels

摘要

Spiropyrans and spirooxazines belong to one of the most fascinating families of photochromic compounds; they undergo reversible structural isomerization between a colorless spiro form and a colored merocyanine upon either light, heat, or chemical stimulus.[1] In organic solvents the conversion-conversion of spiropyran into merocyanine can be induced bycomplexation of a metal ion with cooperative ligation of another chelating functionality attached at the 8’-position.[2] Up to now, a number of such spiropyran receptors have been designed and widely applied for the optical detection of transition-metal and alkali-metal ions.[3] It should be pointed out, however, that despite the large number of reports, spiropyran structures have rarely been used to recognize anions or small organic molecules such as biologically important amino acids. Sunamoto et al.