3D printing of responsive hydrogels for drug-delivery systems

3D printing technology has enabled unprecedented flexibility in the design and manufacturing of complex objects, which can be utilized in personalized and programmable medicine. The aim of this study is to evaluate the potential of 3D printing by digital light processing to fabricate drug-loaded systems with special designs and unique drug-release characteristics, which otherwise are not possible to fabricate by conventional pharmaceutical manufacturing methods. Oral dosage forms of pH responsive hydrogels were 3D printed using acrylic acid monomer, cross-linker (polyethylene glycol diacrylate) and photoinitiator (2,4,6-trimethylbenzoyl-diphenylphosphine oxide [TPO] nanoparticles). Sulforhodamine B, a pH independent fluorescent dye, was used to model a small molecule hydrophilic drug. The printed structures exhibited pH responsive swelling and the effect of pH and tablets' surface area were studied on drug release. The tablets showed higher swelling and faster drug release at higher pH, making them a promising system for enhancing drug absorption in the intestine. Structures with large surface area and complex structures showed enhanced swelling and faster drug release and vice versa.