Enhanced Fluorimetric Determination of Europium with Dibenzoylmethane and Diphenylguanidine by Terbium

A study of the enhanced fluorescence intensity of Eu-dibenzoylmethane(DBM)-diphenylguanidine(DPG) by terbium was made. The excitation and emission wavelengths were 390 and 612 nm, respectively. The fluorescence intensity was a linear function of the concentration of europium in the range 5.0×10−10 −6.0×10−8 M. The detection limit was 5.0×10−11 M. The standard addition method was used for the determination of europium in rare earth oxides.