Formulation and Evaluation of Microemulsions-Based Drug Delivery System for Intranasal Administration of Olanzapine

This paper describes formulation considerations and in vitro evaluation of an oleic acid-based polyelectrolytic polymer-containing microemulsion drug delivery system designed for intranasal administration of a hydrophobic model drug Olanzapine. Drug-loaded microemulsions were successfully prepared by a water titration method. The microemulsion containing 4% oleic acid, 30% surfactant mixture of Labrasol: Cremophor RH 40 (1:1) : Transcutol P (3:1) and 66% (wt/wt) aqueous phase that displayed an optical transparency 99.93%, globule size 25.67 ± 1.17 nm, and polydispersity index of 0.121 ± 0.016 was selected for the incorporation of polyelectrolytic polymer (polycarbophil) as the mucoadhesive component. The mucoadhesive microemulsion formulation of Olanzapine that contains 0.5% polycarbophil (w/w) displayed higher in vitro mucoadhesive potential (19.0 ± 2.0 min) and diffusion coefficient (1.40 × 10 ± 0.019 × 10) than the microemulsion, followed Higuchi model, was free from nasal ciliotoxicity and stable for six months. _____________________________________________________________________________________________________________