Multinozzle low-temperature deposition system for construction of gradient tissue engineering scaffolds

Tissue engineering is a technology that enables us to construct complicated hominine organs composed of many different types of cells. One of the key points to achieve this goal is to control the material composition and porous structure of the scaffold accurately. A disposable syringe based volume-driven injecting (VDI) nozzle was proposed and designed to extrude both natural derived and synthetic polymers. A multinozzle low-temperature deposition and manufacturing (M-LDM) system is proposed to fabricate scaffolds with heterogeneous materials and gradient hierarchical porous structures. PLGA, collagen, gelatin, chitosan can be extruded without leaking to form hierarchical porous scaffolds for primary study. Composite scaffolds with two kinds of materials were fabricated via two different nozzles to get both hydrophilic and mechanical properties. The results from scanning electron microscopy (SEM) demonstrated that the natural-derived biomaterials were strongly absorbed onto the synthetic biomaterials to form a stable network. Several gradient PLGA/TCP scaffolds were also fabricated to supply several samples.