Combining Selective Laser Sintering and Fused Deposition Modeling of Pharmaceutical Polymers: A Novel Approach to Prepare Intestine-Targeted Tablets

Abstract

This study introduces a novel approach to prepare an intestine-targeting transport system with a controlled drug release profile, combining two 3D printing techniques: selective laser sintering (SLS) and fused deposition modeling (FDM). Material evaluations indicate that a mixture of Kollidon^® VA64 with 20% of Kollicoat^® IR and 0.2% of Aeroperl^® has the best flow behavior and exhibits optimal printability at a laser speed of 90 mm s⁻¹. The formulation is subsequently drug-loaded and the printed cores are coated using the FDM technique. The core serves as a drug carrier and the FDM coating shell, consisting of 95% HPMC and 5% pectin, provides modified drug release and enhanced mechanical resistance of the tablet. The coating exhibits acid-resistant properties, with no drug release in the pH of 1.2 during the first 120 min of dissolution testing. In the pH of 6.8, the release profile shows zero-order kinetics with a constant release rate of 0.249% min⁻¹ (in the time interval from 255 to 480 min). At the time point of 720 min, 92% of the drug is released. Dissolution testing thus demonstrates delayed and prolonged drug release. Combining both 3D printing methods shows great potential for personalized treatment of intestinal inflammatory diseases.