QbD steered fabrication of Pullulan-Terminalia catappa-Carbopol®971P film forming gel for improved rheological, textural and biopharmaceutical aspects

In present work, a film forming gel (FFG) was developed through ingenious amalgamation of polymers: Pullulan, Terminalia catappa and Carbopol®971P ® for cutaneous delivery of clotrimazole (CTZ) employing D-optimal mixture design. The developed FFG possess pseudoplastic, viscoelastic, thixotropic characteristics leading to good spreadability (35.71 ± 1.72 g·s, work of shear; 452.73 ± 8.23 g, firmness). Upon solvent evaporation, FFG converted in situ into bioadhesive film (81.90 ± 3.24 g) leading to longer residence on skin surface, prolonged delivery and ~1.3 fold enhanced CTZ skin retention as compare to commercial cream as evident from biopharmaceutical analysis, which is ideal for skin infections treatment. The simulation analysis suggested ≥10 μg/mL (MIC against C. albicans) CTZ concentration maintained for 2 times the days in rat skin as well as human skin as compared to commercial cream. Overall, the developed FFG system ascertained to be promising delivery system for treatment of chronic skin conditions.