Sodium Alginate-Based Microspheres of Salbutamol Sulphate for Nasal Administration: Formulation and Evaluation

Ragwa M. Farid^{1 ⃰}, Mohamed A. Etman², Aly H.Nada³, Abd-Elazeem A. Ebian²

1. Department of Pharmaceutics, Faculty of Pharmacy and Drug Manufacturing, Pharos University, Alexandria, Egypt

2. Department of Pharmaceutics, Faculty of Pharmacy, Alexandria University, Alexandria, Egypt

3. Department of Pharmaceutics, Faculty of Pharmacy, Kuwait University, Kuwait

ABSTRACT

Nasal delivery protects drugs like salbutamol sulphate (SS) from hepatic first-pass metabolism. The study aimed to formulate mucoadhesive sodium alginate (SA) microspheres loaded with (SS) by emulsion cross-linking, with mucoadhesive polymers, for potential nasal delivery by-passing first-pass metabolism. Relevant physichochemical properties, in vitro release and irritation in rabbits were investigated. Stirring rate and cross-linking time affected microsphere parameters. Microspheres were spherical in shape, discrete, with smooth and porous properties favorable for intranasal absorption with high drug-loading of 78.7 %. Mixed-polymers microspheres exhibited higher degree of swelling. Kinetic analysis of release data showed a case II release kinetics for alginate microspheres, and anomalous mechanism for other mixed-polymers formulae. Pronounced sustained drug release over 8 hours was exhibited upon incorporation of Carbopol^® 934 and Hydroxypropyl methyl cellulose. The formulated microspheres showed high swelling ability and good mucoadhesion, offering a good potential for future in vivo study to confirm safety and avoidance of first-pass metabolism.

Keywords: Mucoadhesive microspheres; nasal; salbutamol sulphate; sodium alginate