Enhancing the Oral Bioavailability of Carbamazepine Through Nanosuspension Technology

Carbamazepine is an antiepileptic drug with poor aqueous solubility, which can limit its dissolution and oral absorption. The present study was aimed at developing carbamazepine nanosuspension by the anti-solvent precipitation technique to reduce particle size and improve dissolution characteristics. Carbamazepine nanosuspensions were prepared using ethanol as the solvent and PVP K90, sodium lauryl sulfate (SLS), and Tween 80 as stabilisers. Four formulations (F1–F4) were prepared with different concentrations of stabilisers and evaluated for drug content, viscosity, particle size, polydispersity index (PDI), zeta potential, and in-vitro drug release. Pre-formulation studies including organoleptic properties, melting point, solubility, FTIR spectroscopy, λ max determination, and calibration curve were also performed. Among the formulations, F2 was selected as the optimized formulation. F2 showed 97.20% drug content, 1.77cP viscosity, 153.45nm particle size, and 0.335 PDI. The zeta potential was found to be −32.3mV. Invitro drug release using the egg shell membrane diffusion method showed 89.15% cumulative drug release at 360 minutes. Release kinetics showed the highest R² value for the Higuchi model (0.987). The study indicates that anti-solvent precipitation is a suitable approach for developing carbamazepine nanosuspension with improved dissolution characteristics and potential for enhanced oral delivery.