Nano-scale analytical insights for determination of vonoprazan and aspirin in a recently approved combined preparation utilizing nucleophilic substitution reaction, along with evaluation approaches for both greenness and whiteness

Our study point and emphasis were focused on analysis of vanoprazan (VPZ) and aspirin (ASP) in their newly FDA-approved combination. We were inspired to create this approach by the necessity to discover a green way to analyse tiny nanograms of each drug in a straightforward and sensitive manner. The study developed a first spectrofluorometric approach for determination of VPZ/ASP in their in-lab prepared synthetic mixture and in recently FDA-approved tablets based on two combined methodologies. The first one was based on determination of the native fluorescence of ASP at 405 nm after being excited at 295 nm, without any conflicts from VPZ. The second strategy was based on derivatization of VPZ with NBD-Cl, by nucleophilic substitution of the electroactive chloride in the fluorigenic reagent (NBD-Cl) with the secondary amine in VPZ, to generate NBD-VPZ fluorophore (highly fluorescent) that could be quantified at 537 nm after being excited at 465 nm without any obvious interaction from ASP. Several experimental variables were optimized after several attempts to get the best sensitivity for both determination methodologies. The suggested methods, which exhibit linearity throughout the concentration range of 2.0 - 100.0 ng.mL-1 for ASP and 5.0 - 200.0 ng.mL-1 for VPZ, were shown to be exceptionally sensitive and selective. Additionally, the greenness and whiteness profiles for this approach were evaluated using the GAPI, AGREE, and RGB12 models; the positive results supported their use as great candidates for successful implementation in quality control labs and the pharmaceutical analysis companies.