Kinetic characterization of spiropyrans in aqueous media

Detailed kinetic investigations of the most common photo-switchable spiropyran, 6-nitro-BIPS, reveal that hydrolytic decomposition of its merocyanine isomer limits its utility in aqueous buffer; however, simple replacement of the 6-nitro substituent with an 8-carboxylate yields a BIPS photoswitch that is potentially better suited for biological applications.