Coatings of Ethylcellulose on Drug Loaded Multiparticulates – A Comparison of Rotor Dry Powder Layering to a Wurster Bottom Spray Coating Process
Controlled release coatings of ethylcellulose were applied to drug loaded sugar spheres with three different processes: dry powder layering, aqueous Wurster coating and organic solvent based Wurster coating. Comparative analysis of the three processes showed that the dry powder layering process was able to apply the ethylcellulose coatings in a faster, more efficient process than the traditional spray coating systems and still achieve controlled release.