Development and Validation of a Terbium-Sensitized Luminescence Analytical Method for Deferiprone

A sensitive fluorometric method for the determination of deferiprone (DFP) based on the formation of a luminescent complex with Tb3+ ions in aqueous solutions is reported. The maximum excitation and emission wavelengths were 295 and 545 nm, respectively. The effects of various factors on the luminescence intensity of the system were investigated and optimized, then under the optimum conditions, the method was validated. The method validation results indicated that the relative intensity at 545 nm has a linear relationship with the concentration of DFP in aqueous solutions at the range of 7.2 × 10-9 to 1.4 × 10-5 M, the detection and quantification limits were calculated respectively as 6.3 × 10-9 and 2.1 × 10-8 M, precision and accuracy of the method were lower than 5% and the recovery was between 100.1% and 102.3%. The results indicated that this method was simple, time saving, specific, accurate and precise for the determination of DFP in aqueous solutions. After optimization and validation, the method successfully applied for determination of DFP in tablet dosage forms. The stoichiometry of the Tb3+-DFP complex was found as 1:3 and the complex formation constant was 1.6 × 1016.