Fabrication, optimization, and eco-friendly micellar HPLC determination of Alogliptin/Dapagliflozin pullulan-based sublingual films for therapeutic efficacy improvement in diabetic rats

The aim of this study was to prepare and statistically optimize a pullulan-based sublingual film containing Alogliptin/Dapagliflozin (ALO/DAPA) mixture, by solvent casting technique to provide a promising remedy for type 2 diabetes. Sublingual films were optimized by employing a central composite design created by the Design Expert® software. The optimized formula was further determined using a novel eco-friendly micellar HPLC method. The separation was carried out on a Kinetex C18 column (100 mm × 4.6 mm i. d, 2.6-μm particle size) with isocratic elution at a flow rate of 1 mL/min and UV detection at 230 nm. The micellar aqueous mobile phase used for the separation was composed of 50 mM sodium dodecyl sulfate, 15% pentanol, and 50 mM sodium dihydrogen phosphate (pH 3.5). The antidiabetic effects of ALO/DAPA sublingual films on the blood glucose levels of diabetic rats and their effect on the pancreas and kidney histopathology were studied. The developed method was accurate, and precise and can be used for the simultaneous estimation of both drugs without any interference in their sublingual films. Moreover, the greenness of the suggested method has been evaluated by different tools; analytical Eco-scale and the Green Analytical procedure Index, which shows that it has the least environmental impact. The ALO/DAPA sublingual film optimal formula showed mechanical strength of 2.69 ± 0.23 N/mm2, folding endurance of 69 ± 2.13 times, and in-vitro disintegration of 71.7 ± 1.23 s indicating acceptable formulation and mechanical parameters. A significant improvement in glycemic control where the blood glucose level was normalized (137 ± 23) after 4 h compared to the commercial drugs (247 ± 27.4) at p