Luminescent europium tetraazamacrocyclic complexes with wide range pH sensitivity

Abstract

The complexes [EuL¹]³⁺ and [EuL²] function as luminescent pH sensors over an extended pH range; two distinguishable pH switching ranges are observed: the delayed europium emission is switched on in acidic solution, whereas the fluorescence emission spectra show a pronounced pH dependence only in alkaline media.

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