Abstract
Recently, supersaturable self-nanoemulsion (Su-SNE) is an advanced approach that can address low oral bioavailability issues. The antihypertensive drug, nebivolol (NBH), has low bioavailability, about 12%, due to its poor solubility and extensive pre-systematic metabolism. This work aimed to convert liquid nebivolol Su-SNE to powder using a liquisolid technique for exploiting the privileges of both Su-SNE and liquisolid approaches. Liquid NBH-loaded Su-SNE composed of imwitor 988, cremophor EL, propylene glycol and soluplus was adsorbed onto avicel PH101 and aerosil 200 admixture. The powder flow properties and in-vitro dissolution tests were carried out. Furthermore, the solid-state of optimized formula was characterized by SEM, DSC, X-ray diffraction, FT-IR analysis, and mean droplets size after redispersion in 0.1N HCl. The optimum liquisolid formula (SL-F8) revealed good flowability and significant dissolution improvement with 98.8% ± 0.99 drug dissolved compared to 23.1% ± 1.5 of pure NBH at 60 min. The solid-state characterization study of formula (SL-F8) showed an amorphous state of NBH within the solidified nanosystem without any interactions with the excipient used. Also, it gave nanoemulsion with mean droplets size about 47.77nm ±1.58 and PDI 0.289± 0.03, which was close to liquid Su-SNE with 55.27nm ± 1.22 droplets size and PDI 0.294± 0.01. Consequently, the liquisolid technique is a promising strategy for solidification of a liquid self-emulsifying system with improving dissolution rate and maintaining nanoemulsion properties.

Key words: Avicel PH101, dissolution efficiency, liquisolid powder, supersaturable self-nanoemulsion