Preparation and characterization of novel fast disintegrating capsules (Fastcaps) for administration in the oral cavity

The objective of this study was to prepare novel capsule-based fast disintegrating dosage forms for the oral cavity (Fastcaps). First, cast films were prepared from various additive-containing gelatin solutions and evaluated with respect to disintegration time and mechanical properties in order to identify suitable formulations for the capsule preparation. The disintegration time of films decreased with decreasing bloom strength and could be further decreased by the addition of sugars or PEGs. Fast disintegrating capsules were successfully prepared by a dipping process, whereby parameters such as the viscosity and temperature of the dipping solution and the dipping velocity of the steel pins were optimized. The required viscosity range of the dipping solution for Fastcap manufacturing was 500–600 cP. The addition of the hydrophilic additives (xylitol, sorbitol or PEG 1500) did not significantly affect the viscosity and gelation temperature of the dipping solution. The in vitro disintegration of Fastcaps (30–45 s) was twice as rapid as the one of regular hard gelatin capsules. In vivo, Fastcaps disintegrated rapidly (9–13 s) and their content was spread throughout the oral cavity within seconds. Lactose and/or microcrystalline cellulose were suitable fillers for Fastcaps. The mechanical properties of Fastcaps were similar to commercially available gelatin capsules, which assures good processability and handling.