A selective fluorescent bulk sensor for lutetium based on hexagonal mesoporous structures

Abstract A novel Lu 3+ sensitive fluorescent chemosensor is constructed by preparation of 8-hydroxyquinoline functionalized mesoporous silica with ordered hexagonal array structure (SBA-SPS-Q). The new synthesis material demonstrated a selective interaction with Lu 3+ ion, most probably because of the presence of the fluorophore part at its surface. Fluorescence studies revealed that the emission intensity of the Lu 3+ -bound mesoporous material increases significantly after addition of various concentrations of Lu 3+ , while the mono-, di-, trivalent cations result in either no changes or weak changes in fluorescent intensities. The enhancement of fluorescence is attributed to the strong covalent binding of Lu 3+ ion, evident from the large binding constant value (2 × 10 6  M −1 ). The linear range of the fluorescent chemosensor covers a Lu 3+ concentration from 1.6 × 10 −7 to 2.6 × 10 −6  M, with detection limit of 4.0 × 10 −8  M. This chemosensor has been applied to determination of Lu 3+ ion in some soil samples where domestic devices were stored.