Assessment of the greenness of new stability indicating micellar UPLC and HPTLC methods for determination of tenofovir alafenamide in dosage forms

Abstract

In this study, a green stability indicating chromatographic methods were developed and validated for the quantitative determination of tenofovir alafenamide in the presence of its degradation products in bulk powder as well as in dosage forms. The first method was micellar UPLC in which separation was achieved on kinetex ® 1.7 μm HILIC 100A, LC column using an ecofriendly micellar mobile phase consisting (0.05 M sodium dodecyl sulphate and 0.05 M sodium dihydrogen phosphate, (pH 5.5) and 10% 1-propanol (70:30) at a flow rate of 1 mL min-1 with a UV detection at 210 nm. The second method depended on HPTLC method performed on HPTLC plates pre-coated with silica gel 60 F254 using a mobile phase consisting of n-butanol-acetic acid (7:3, v/v) and detection at 260 nm. Tenofovir alafenamide was subjected to stress conditions including alkaline and acidic degradation. Beer' law was obeyed over the concentration range of 1-18 μg mL-1 and 0.1-4 μg/spot for micellar UPLC and HPTLC methods, respectively. Both methods are successfully applied to the analysis of the drug in its tablets and validated according to ICH guidelines. In addition, their greenness was assessed using three different tools indicating their least hazardous effect on the environment.