Exploration of FDM 3D-printed multi-compartment drug delivery devices: structural modulation of release kinetics for...

Fused deposition modeling (FDM) 3D printing enables fabricating complex drug delivery devices with tailored geometries. This study explored structural modulation in FDM-printed multi-compartment devices (capsules and tablets) to achieve precise control over drug release kinetics, including pulsatile and near-zero-order release patterns, for personalized therapy.

Multi-compartment devices with varying configurations and wall thicknesses were fabricated using polyvinyl alcohol (PVA) filament via FDM 3D printing. The physical properties, geometrical accuracy, thermal properties, sealability, and mechanical strength of the printed devices were characterized. In vitro drug release studies were conducted using dyes and caffeine as a model drug, and release profiles were analyzed using kinetic models.

The PVA erosion rate showed a strong linear relationship with time (R² = 0.967). A strong linear correlation (R² > 0.95) existed between the compartment wall thickness and the onset time of drug release, allowing programmed pulsatile release. Multi-compartment capsular devices produced sequential, rapid-release pulses, while gradient-thickness tablet devices achieved near-zero-order release kinetics best described by the Peppas model (R² = 0.973, n ≈ 1.12, Super Case-II Transport). Device fabrication demonstrated high dimensional accuracy and reproducibility. Interlayer bonding influenced flexural strength, though all devices met standard requirements.

Structural design, particularly wall thickness, effectively modulates drug release profiles in FDM-printed devices. This geometry-based programming highlights 3D printing's potential for manufacturing personalized drug delivery systems tailored to specific therapeutic needs.