Visible Light Controlled Aggregation of a Spiropyran‐HSO4− Complex as a Strategy for Reversible Detection in Water

Abstract

AbstractA merocyanine salt form of a substituted spiropyran was synthesized and evaluated for stimuli‐responsive properties. The HSO4− induced H‐aggregation of the merocyanine salt was used as a strategy for detection in pure water. The anion induced aggregation was controlled by light, which converted the open merocyanine form into the closed spiropyran form. The formation of the closed form released the hydrogen sulfate ion. The DLS and TEM analyses were used to investigate the aggregation and disaggregation of the merocyanine salt form of a spiropyran. Therefore, the study establishes the first example of reversible, highly selective and nanomolar level response towards HSO4− ion in water.