Development of Three-Dimensional Alginate Encapsulated Chondrocyte Hybrid Scaffolds Using Microstereolithography

Hydrogels are useful materials because of their chemical similarity to extracellular matrix and their ability to rapidly diffuse hydrophilic nutrients and metabolites. Using rapid prototyping (RP) methods, we fabricated freeform three-dimensional (3-D) scaffolds with chondrocytes encapsulated in an alginate hydrogel. The 3-D hybrid scaffold was developed as combination of two components, a TMC/TMP framework and an alginate hydrogel within an encapsulation of chondrocytes. To develop 3-D hybrid scaffolds, we employed a microstereolithography system. The biodegradable, photo-polymerizable liquid prepolymer was prepared by the polymerization of trimethylene carbonate (TMC) with trimethylolpropane (TMP), and subsequently end-capped with an acrylate group. The meshed framework of scaffolds withstood mechanical loading effectively. The line depth and line width could be controlled by varying laser power, scan path, and scan speed. Results of cell culture indicate that the biomimetic nature of these encapsulated chondrocyte scaffolds effectively retain the phenotypic function of chondrocytes within the scaffold structure. The proposed 3-D hybrid scaffolds can be used for cartilage regeneration.