Fluorescent PET (photoinduced electron transfer) sensors selective for submicromolar calcium with quantitatively predictable spectral and ion-binding properties

Abstract

The anthracene (QCa1) and pyrazoline (QCa2) derivatives display Ca²⁺- induced enhancements of fluorescence quantum yields (ϕ_F), by factors of 16 and 92, respectively; the binding selectivities (vs. Mg²⁺ and H⁺) and characteristics of the electronic (absorption and emission) spectra (except ϕ_Fmax.) are reasonably predictable from simpler model compounds.