Люмінесцентне визначення долутегравіру натрію в таблетках

Abstract

The quality control of pharmaceuticals, food products and environmental objects is a topical task of analytical chemistry and is carried out using various methods, often using complex compounds as analytical forms. In recent years, in the pharmaceutical analysis, complex compounds of lanthanide ions are widely used in medicinal products that can sensitize 4f-luminescence, for their highly sensitive determination in dosage forms and in biological fluids. Dolutegravir sodium (DN) is an integrase inhibitor that is meant to be used as part of combination therapy for the treatment of HIV. The sensitized luminescence of Eu(III) ions in complexes with dolutegravir sodium have been investigated (λex = 290 nm; λlum = 612 nm). Optimum concentration and acid-basic conditions of complex Eu:DN=1:1 formation has been established. Ilum is maximum at pH 7.5 (urotropine buffer). The absorption spectrum of DN in water characterized by intense bands in the UV region of the spectrum with maxima at λ = 252 nm and λ = 325 nm. A ratio of the energy of triplet state of the ligand (18000 cm-1) and the first emitting level of Eu(III) ion (17300 cm-1) as well as high extinction coefficients of DN determine the high intensity of a 4f-luminescence (Ilum) of complex. The excitation spectra and luminescence spectra have been recorded on a spectrofluorimeter Cary Eclipse «Varian». Electronic absorption spectra have been recorded on a spectrophotometer UV-2401 PC «Shimadzu». Influence of organic solvents, amount and nature of surfactants on Ilum of the complex has been investigated. Complex Eu(III)–DN was proposed to use as the analytical form for the luminescence determination of DN. Calibration curve was linear over the concentration range of the dolutegravir sodium 0.44-13.2 μg/ml. The developed method was validated on the following parameters: specificity, linearity, precision, limit of quantification. The developed method can be recommended for the determination of DN in tablets. Keywords: sensitized luminescence; еuropium; dolutegravir sodium; tablets.