Development of optimal printability properties of personalized mucoadhesive oral films suitable for extrusion-based 3D food printing depending on temperature

Abstract

Mucoadhesive oral films (MOFs) fabricated by embedding-based three-dimensional (3D) printing require separate matrix and ink materials, leading to complex processes and poor mechanical stability that limit precise additive manufacturing. This study aimed to develop temperature-dependent, extrusion-based 3D printing MOFs capable of balancing flowability and shape retention. Hydroxypropyl methylcellulose (HPMC), agar, and gelatin were compared as thermoresponsive hydrocolloids to identify optimal compositions exhibiting controllable viscoelastic transitions. Rheological analysis revealed that the HPMC–agar blend provided the most stable thermal behavior, where the rapid aggregation of HPMC during heating was moderated by the gradual helix reformation of agar during cooling. A 2:1 HPMC:agar ratio (24 % solids) operated around 70 °C exhibited a single crossover point and a broad transition zone, ensuring continuous extrusion and stable layer stacking. Curcumin incorporated using the amorphous solid dispersion (ASD) method retained approximately 35 % higher antioxidant activity than raw curcumin, demonstrating improved thermal and oxidative protection. Moreover, modulation of digital printing parameters—such as infill density, size, and layer number—allowed predictable control of curcumin content and disintegration onset time for personalization. The results establish a temperature-tunable and compositionally stable formulation strategy for personalized MOF fabrication applicable to functional foods and customized oral delivery systems.