Clicking fluoroionophores onto mesoporous silicas: a universal strategy toward efficient fluorescent surface sensors for metal ions.

Mesoporous SBA-15 silica is an excellent support for constructing fluorescent surface sensors. In this letter, we reported a two-step surface reaction involved strategy to construct efficient fluorescent surface sensors for metal ions by clicking fluoroionophores onto azide-functionalized SBA-15. Our experimental results indicate that such a strategy exhibits an obviously higher loading efficiency within commercial SBA-15 than a previously reported strategy. As a proof-of-concept, a newly designed alkyne-functionalized Hg(2+) fluoroionophore was grafted onto SBA-15 to form a fluorescent Hg(2+) surface sensor. It shows improved sensitivity and selectivity than the fluoroionophore itself working in the solution phase with a detection limit of 2.0 x 10(-8) M for Hg(2+).