Adopted green spectrophotometric determination of futibatinib based on diazo coupling with 1-naphthol and assisted computational calculations

Futibatinib, a potent fibroblast growth factor receptor inhibitor, received US approval on September 30, 2022, for treating breast, esophageal, and lung cancers by reducing cell viability. A new spectrophotometric method has been developed to accurately quantify this drug with the use of computational tools and matching environmentally friendly (green) principles. 1-Naphthol was found to be the best reagent for diazo-coupling of futibatinib based on the density functional theory calculations. The experimental process involves diazo coupling futibatinib with sodium nitrite to produce a diazonium ion, which then interacts with 1-Naphthol to develop a red-colored chromogen complex. At 514 nm, the resultant complex displays defined measurable quantitative absorption peaks. A number of elements that affect the diazotization were researched in order to optimize the process. The method exhibited excellent linearity within the range of 1–12 μg/mL (r² = 0.9996), with limits of detection and quantification at 0.10 μg/mL and 0.30 μg/mL, respectively. It also demonstrated high accuracy (99.32 %) and precision (%RSD < 1). The proposed method has a greener profile, scoring 0.69 compared to 0.48 for previously reported UPLC-MS/MS methods, offering reduced waste, shorter analysis times, and lower energy consumption. Additionally, it is more cost-effective and environmentally sustainable, making it a viable choice for both pure and pharmaceutical applications.