Olmesartan medoxomil loaded niosomal gel for buccal delivery: Formulation, optimization, and ex vivo studies

INTRODUCTION: Olmesartan medoxomil (OLM) is a low bioavailability antihypertensive drug. This study was aimed to prepare and optimize an OLM niosomal gel and investigate the drug permeation via a chicken buccal pouch.
METHODS: OLM loaded niosomes were prepared using a film hydration technique. The vesicle size, zeta potential, entrapment efficiency, and percentage cumulative drug release of niosomes were evaluated. The niosomes were incorporated into a Carbopol 974P (1.5 percent w/v) gel and drug permeability of niosomal gel was evaluated. The formulations of the niosomal gel were optimized using the Box-Behnken design.
RESULTS: The optimized formulation was further characterized using transmission electron microscopy (TEM) and FTIR analysis. The particle size and zeta potentials of optimized niosomal formulations were found to be 296.4 nm and -38.4 mV, respectively. Based on TEM analysis, the niosomes were found spherical in shape. The permeability, flux, and permeability coefficient of optimized niosomal gel was found to be 0.507 mg/cm2, 0.083 mg/cm2×h, 041 cm/h, respectively. The histopathology evaluation revealed that the niosomal gel had better permeability compared to OLM gel.
DISCUSSION AND CONCLUSION: Based on the results of the OLM niosomal gel, it can be concluded that the formulation can be beneficial in increasing the bioavailability, resulting in better therapeutic efficacy.