EVALUATION OF DRUG LAYERING AND COATING - EFFECT OF PROCESS MODE AND BINDER LEVEL

Top-spray layering and Wurster coating are common techniques for layering and coating operations, respectively. In the present study, the efficiency of these techniques was compared with rotolayering and rotocoating in the Niro-Aeromatic MP-1 Rotoprocessor. Also, three different polymers were evaluated as binding agents in the layering procedure. A solution containing drug and a suitable binder was layered onto non-pareil seeds followed by coating with a water-insoluble polymer. The pellets were evaluated for physical properties, surface characteristics and drug content (assay) . The process efficiency was evaluated from process time, assay, and SEM data of the pellets. Efficiency of layering was compared between toplayering and rotolayering processes while efficiency of coating was compared between Wurster coating and rotocoating processes. The physical properties of pellets were used to explain the influence of binder nature and level of use in the layering process.