Analysis of Two Oncological Drugs Futibatinib and Capivasertib via Ion‐Pairing With Eosin Y as a Spectrofluorimetric and Spectrophotometric Probe

Using spectroscopy, two quick and sensitive analytical methods based on eosin Y ion pairing were developed and assessed in order to determine capivasertib and futibatinib with high selectivity and sensitivity. The quenching impact of futibatinib or capivasertib on the eosin Y's fluorescence at a pH 3.8 and 3.3 for futibatinib and capivasertib, respectively, in 0.1-M acetate buffer solution was observed using two spectrofluorometric techniques. These techniques are regarded as the original spectrofluorometric techniques for the assay of futibatinib and capivasertib. For futibatinib and capivasertib, the quenching effect on fluorescence was ranged from 100 to 1000 and 150 to 1500 ng mL^-1, respectively. The absorbance of the generated ion-pair was measured using two different spectrophotometric methods at 550 nm in aqueous buffered solutions with pH values of 3.8 and 3.3 for futibatinib and capivasertib, respectively. In the concentration range of 1.0-10.0 and 2.0-10.0 μg mL^-1, Beer's law was followed. The four approaches were applied to the analysis of dosage forms with a high percent recovery successfully, and they were assessed in compliance with ICH guidelines.