Detection of Cu^II by a chemodosimeter-functionalized monolayer on mesoporous silica

An anthraquinone-containing chemodosimeter and its mesoporous silica-immobilization anthraquinone (MISA) was designed, which was responsible for Cu²⁺-induced desulfurization followed by cyclization to provide highly selective UV and fluorescence changes. The results show that the introduction of Cu²⁺ ions induces a distinct blue-shift in the UV absorption band, while no significant spectral changes are observed upon addition to other metal ions. The addition of Cu²⁺ ions also provide higher selectivity over other metal cations to give an emission band shift from 590 to 555 nm, along with increasing intensity. TEM images of MISA show the formation of a well-ordered hexagonal arrangement of mesoporous channels before and after attaching. The adsorption ability of MISA for metal cations show that Cu²⁺ is selectively adsorptive.