Indirect spectrofluorimetric determination of mosapride citrate in pharmaceutical formulations

New europium complexes of 3-oxo-1-hydroxy-quinoline-2-carboxylic acid amide derivatives (L1-L3), which are highly luminescent and do not require luminescence enhancers are reported. The luminescence intensity of the Eu-L1-3 complexes was enhanced by the addition of citrate ions in water solution. A sensitive luminescence enhancement system was developed for the determination of citrate ions on the base of Eu-9-fluoro-1-hydroxy-5-methyl-3-oxo-6,7-dihydro-3H,5H-pyrido[3,2,1-ij]quinoline-2-carboxylic acid (2-piperazin-1-yl-ethyl)-amide (L1) complex. This effect was applied to the determination of the drug, which is not a lanthanide luminescence sensitizer. The Eu-L1- Cit complex with a components' ratio 1:1:2 was proposed to be used as the analytical form for the luminescence determination of drug - mosapride citrate. The calibration curve is linear in the range of 1.0-25.0 microg/mL of mosapride citrate (LOD is 0.35 microg/mL). This method was applied for the determination of mosapride citrate in dosage form - tablets "Mosid MT" - 2.5 mg.