title: Enteric coating of soft gelatin capsules by spouted bed: effect of operating conditions on coating efficiency and on product quality.
abstract: The present study was conducted in order to analyze the viability of the spouted bed process for application of a gastric-resistant coating to soft gelatin capsules. The variables investigated were: included angle of conical base, (gamma), the relation between the feed mass flow rate of the coating suspension and the feed mass flow rate of spouting gas (W(s)/W(g)); the ratio between the flow rate of the spouting gas and the flow rate at minimum spouting condition (Q/Q(ms)); the mass of capsules in the bed (M(0)), and the capsule's size. The product quality was measured by disintegration tests, traction x deformation tests, image analysis and by the evaluation of the coating mass distribution and shape factor variation during the coating operation. The experiments were performed in a spouted bed with a column diameter of 200 mm and included a conical base angle of 40 degrees. The best coating efficiency values were obtained for M(0)=300 g. Coating efficiency tended to increase with increasing W(s)/W(g) ratio. Disintegration tests showed that the gastric-resistant effect was obtained with a coating mass of 3.86 mg/cm(2). The shape factor increase during the coating operation. The capsule's coating mass distribution tended to maintain the original distribution.
authors.affiliation: Faculdade de Ciências Farmacêuticas de Ribeirão Preto/USP, SP, Ribeirão Preto, Brazil.
authors.forename: Rafael
authors.initials: R
authors.lastname: Pissinati
authors.forename: Wanderley Pereira
authors.initials: WP
authors.lastname: Oliveira
mesh_terms: D002214:Capsules / Q000138:chemical synthesis / Q000592:standards*; D005780:Gelatin / Q000138:chemical synthesis / Q000592:standards*; D013608:Tablets, Enteric-Coated / Q000138:chemical synthesis / Q000592:standards*; D013678:Technology, Pharmaceutical / Q000295:instrumentation / Q000379:methods / Q000592:standards*
chemical_list: D002214:Capsules; D013608:Tablets, Enteric-Coated; D005780:Gelatin