3D printing of hollow capsular body & sealing pin by fused filament fabrication (FFF) technique using Kollicoat MAE 100P filament for intestinal specific delivery

Additive manufacturing (AM) is an emerging pharmaceutical manufacturing technique feasible for patient-centric personalised medicine with tailored pharmacotherapy. Fused filament fabrication (FFF) is a highly emphasised 3D printing technology because it is highly economical and user friendly. However, bridging fused filament fabrication with hot-melt extrusion for filament synthesis is one of the crucial steps involved. This study highlights the feasibility of prototyping a diclofenac sodium-filled enteric hollow compartmental device to avoid gastric irritation associated with the drug. Furthermore, for the first time Kollicoat MAE100P was evaluated for its extrudability in hot-melt and printability during fused filament fabrication. A novel hollow compartmental device was designed with improved sealing conditions, unlike conventional capsules.

An optimistic printable filament was extruded using triethyl citrate (TEC) and talc as plasticiser and filler, respectively. The thermal and chemical stabilities of the polymers were confirmed by DSC and FTIR analyses, respectively. The final layer-by-layer printed drug-filled hollow compartmental device was evaluated for its morphology and in vitro enteric release behaviour at pH 6.8, showing a complete release within 4 h with a lag period in an acidic environment of pH 1.2 and the release kinetics fit well with first-order kinetics (R² > 0.9522). The gastric resistance of the hollow compartmental device was confirmed by in vivo pharmacokinetic assessment, which revealed a 30-min lag phase of the drug release and obtained PK parameters compiles for the delayed release phenomenon.

This study revealed the possibility of fabricating a hollow compartmental device with an improved sealing effect using Kollicoat MAE100P by combining FFF with the melt extrusion process. The results showed that the designed hollow compartmental device provided intestinal release, successfully bypassing release in an acidic environment.