DOE-BASED FORMULATION AND CHARACTERIZATION OF NIFEDIPINE-LOADED SMEDDS EMBEDDED IN FAST DISSOLVING FILMS FOR IMPROVED ORAL BIOAVAILABILITY

Objective: Nifedipine (NIFD), a calcium channel blocker with poor aqueous solubility and low oral bioavailability, requires formulation enhancement for effective delivery. This study aimed to develop and optimise a Self-Microemulsifying Drug Delivery System (SMEDDS) of NIFD and incorporate it into mouth-dissolving films (MDFs) to improve solubility, dissolution, and patient compliance. Methods: Box-Behnken Design (BBD) was employed to optimise SMEDDS formulations using castor oil (A), Tween 80 (B), and Span 80 (C) as factors, with droplet size (Y1) and transmittance (%) as responses. The optimised SMEDDS batches (FS14-FS16) were characterised for droplet size, PDI, zeta potential, and transmittance and subsequently incorporated into MDFs (F1-F3) by solvent casting. Results: The optimised SMEDDS exhibited droplet sizes between 196-201 nm, PDI values of 0.534-0.608, and zeta potentials from -15.66 to -21.07 mV, indicating nanoscale dispersion and moderate stability. The resulting SMEDDS-loaded films (F1-F3) showed uniform thickness (0.11-0.15 mm), rapid disintegration (48-60 s), and high drug content (87.04-95.08%). The diffusion of NIFD increased by a factor 3 after incorporating it into SMEDDS. Conclusion: The optimised nifedipine-loaded SMEDDS (FS14-FS16) successfully incorporated into mouth-dissolving films (F1-F3), significantly enhanced solubility and dissolution. Among the MDFs, , F1 emerged as the best demonstrating superior in vitro drug release compared to the pure nifedipine film, offering a promising oral delivery system for enhancing the bioavailability of poorly soluble drugs.