Colon-targeted 3D-Printed mesalamine tablets: Core-shell design and in vitro/ex-vivo evaluation

The present study is intended to develop a shell-core tablet using a hot melt extrusion (HME)-based dual-nozzle fused deposition modeling (FDM) three-dimensional (3D) printing approach. The primary objective was to establish a sustained-release colonic drug delivery system and improve mesalamine's permeability by incorporating Vitamin E TPGS as a permeation enhancer. The study utilized Kollidon® SR for sustained release, L-100, and HPMC HME L100 for the tablet's protective shell. Six filament formulations were tested, and the mechanical properties of the shell filaments, including the three-point bending, Hooke's law, and stiffness, were assessed. Drug release profiles of the tablets were evaluated using the USP-II dissolution apparatus, and permeability characteristics were gauged using the non-everted intestinal sac method. Solutions containing 5% w/v mesalamine and 2.5% w/v Vitamin E TPGS were employed, with pure mesalamine as a control. Optimal filament ratios were identified as 50:50 for the core and 30:70 for Eudragit L-100 to HPMC HME L100 for the shell. The resulting tablets achieved a prolonged drug release of up to 24 h for the core. They ensured minimal drug release in the upper gastrointestinal tract (∼5% in the first 5 h), effectively targeting the colon. Incorporating Vitamin E TPGS led to a 3.6-fold increase in mesalamine absorption compared to the control, and the addition of Kollidon® SR notably improved the flow properties of Mesalamine powder. In conclusion, this innovative approach has the potential to achieve a colon-specific drug delivery system. [Display omitted] •Integrating HME with FDM 3D printing signifies an innovative approach for colonic drug delivery.•Vitamin E TPGS enhanced mesalamine permeability.•Shell filament produced via hot-melt extrusion (HME) and 3D printed to ensure protection of the core tablet.