Three-dimensional (3D) printed tablets using ethyl cellulose and hydroxypropyl cellulose to achieve zero order sustained release profile

The main objective of this study was to investigate the potential of coupling hot-melt extrusion (HME) and 3D printing in order to design drug containing matrix tablets for the purpose of achieving zero order release. The effect of the blend ratio of ethyl cellulose (EC) and hydroxypropyl cellulose (HPC), carbamazepine (CBZ) as a model drug and triethyl citrate (TEC) on the mechanical and printability properties of extruded filaments was investigated. Filament formulation containing CBZ, EC and HPC (3, 64.7 and 32.3% w/w, respectively) and 20% w/w of TEC (by weight on the dry powder) showed optimum mechanical and printability properties and subsequently was printed into tablets (370 mg, 13 mm diameter, 3.5 mm thickness, cylinder-shaped) at 187 degrees C. The printed tablets showed good uniformity in drug content and appropriate mechanical properties. The optimum filament showed first order drug release pattern, while the 3D printed tablets showed zero-order drug release and slower drug release rate than the optimum filament. Overall, we have demonstrated that zero order release tablets can be prepared from a 2:1 ratio of EC to HPC, by combination of HME and 3D printing technologies with the capability of reducing dose frequency and adverse effects of drugs.