Salbutamol sulfate (SS), a direct acting sympathomimetic; used for the treatment of acute and chronic asthma, was formulated as gelerite® in-situ gels. SS in-situ gels (2% w/w) were prepared at concentration of gellan gum 0.2%, 0.4% and 0.8% w/v with methyl paraben (0.05%) as preservative. In-vitro release in simulated nasal fluid showed relatively fast release and release kinetics followed diffusion kinetic model. In-vivo mucoadhesiveness test performed in rats, showed prolonged mucociliary transport time from 5 min (control solution) to 16.5 and 19.5 minutes for formulations containing 0.4% & 0.8% respectively. In-situ gels have demonstrated an adequate safety to the nasal mucosa of rats. The 0.4 % in-situ gel remained liquid for 6 months without occurrence of turbidity or gelation at storage temperature conditions. Statistical analysis revealed non-significant difference in content uniformity or release compared to the fresh ones. In-situ gel is a promising approach for the intranasal delivery of SS, combines the advantage of a solution , administration convenience and exact dosing with favorable residence time and expected improved drug absorption. .
Abd-Elazim Rafaat Ebian, Mohamed Ahmed Etman, Ragwa Farid Mansour