Sustained-release floating drug delivery systems prepared using three-dimensional printing

Sustained-release floating drug delivery systems (FDDSs) enable prolonged and continuous input of the drug to the upper parts of the gastrointestinal tract have been designed and fabricated using three dimensional printing (3DP) technology. A new strategy is proposed for the development of FDDSs. The design of FDDSs was based on the sustained release formulation, with low density and floating features in order to prolong the gastric retention time, with special surface textures and variations of drug distribution in the FDDSs for constant release profiles. The local variations of drug in the FDDSs were traced by methylene blue. To measure the floating force, a novel apparatus was developed. Duration of buoyancy and drug release profiles were determined in vitro. It was found that FDDSs were able to float on the dissolution medium 12h, which was the whole tests time periods, and free out the model drug metformin hydrochloride in a way of near zero-order kinetics. 3DP is able to offer possibility for developing FDDSs with complicated design features for providing long-time gastro-retention and desired drug release profiles.