A highly selective fluorescence sensor for Tin (Sn4+) and its application in imaging live cells

Abstract

A naphthalimide–rhodamine B derivative was synthesized as a fluorescence turn-ON chemodosimeter for Sn⁴⁺. A colour change and marked enhancement of fluorescence was found in the presence of Sn⁴⁺, Cu²⁺ and Cr³⁺ due to the ring open reaction of rhodamine and a fluorescence resonance energy transfer process. Addition of the strong chelating agent ethylenediaminetetraacetic acid disodium salt (EDTA) partly released the cation from the complex with Sn⁴⁺ and restored the yellow fluorescence. In addition, the compound can be used as a fluorescent probe for Sn⁴⁺ in biological systems and may act as a tool with which to study the physiological functions of tin or pathogenesis in the human body.