title: Injection-molded capsular device for oral pulsatile release: development of a novel mold.
abstract: The development of a purposely devised mold and a newly set up injection molding (IM) manufacturing process was undertaken to prepare swellable/erodible hydroxypropyl cellulose-based capsular containers. When orally administered, such devices would be intended to achieve pulsatile and/or colonic time-dependent delivery of drugs. An in-depth evaluation of thermal, rheological, and mechanical characteristics of melt formulations/molded items made of the selected polymer (Klucel® LF) with increasing amounts of plasticizer (polyethylene glycol 1500, 5%-15% by weight) was preliminarily carried out. On the basis of the results obtained, a new mold was designed that allowed, through an automatic manufacturing cycle of 5 s duration, matching cap and body items to be prepared. These were subsequently filled and coupled to give a closed device of constant 600 μm thickness. As compared with previous IM systems having the same composition, such capsules showed improved closure mechanism, technological properties, especially in terms of reproducibility of the shell thickness, and release performance. Moreover, the ability of the capsular container to impart a constant lag phase before the liberation of the contents was demonstrated irrespective of the conveyed formulation.
authors.affiliation: Dipartimento di Scienze Farmaceutiche, Sezione di Tecnologia e Legislazione Farmaceutiche M.E. Sangalli, Università degli Studi di Milano, Milano 20133, Italy. lucia.zema@unimi.it
authors.forename: Lucia
authors.initials: L
authors.lastname: Zema
authors.forename: Giulia
authors.initials: G
authors.lastname: Loreti
authors.forename: Elena
authors.initials: E
authors.lastname: Macchi
authors.forename: Anastasia
authors.initials: A
authors.lastname: Foppoli
authors.forename: Alessandra
authors.initials: A
authors.lastname: Maroni
authors.forename: Andrea
authors.initials: A
authors.lastname: Gazzaniga
mesh_terms: D000284:Administration, Oral; D002214:Capsules; D002482:Cellulose / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000737:chemistry / Q000493:pharmacokinetics; D002626:Chemistry, Pharmaceutical / Q000379:methods*; D016503:Drug Delivery Systems / Q000295:instrumentation* / Q000379:methods* / Q000639:trends; D007267:Injections; D012212:Rheology
chemical_list: D002214:Capsules; D002482:Cellulose; C008079:hydroxypropylcellulose