Micro-particle fabrication for tissue engineering applications using rapid prototyping and soft lithography principles

The goal of this study was to develop an efficient and repeatable process for fabrication of micro-particles from multiple materials using rapid prototyping and soft lithography. Phase change three-dimensional printing was used to create masters for PDMS molds. A photocrosslinkable polymer was then delivered into these molds to fabricate geometrically complex three-dimensional micro-particles. This repeatable process has demonstrated the ability to generate micro-particles with greater than 95% repeatability with complete pattern transfer. This process was illustrated for three shapes based on the extrusion of two-dimensional shapes. These particles will allow for tailoring of the pore shapes within a porous scaffold utilized in tissue engineering applications. In addition, the different shapes may allow control of drug release by varying the surface to volume ratio, which could modulate drug delivery. While soft lithography is currently used with photolithography, its high precision is offset by high cost of production. The employment of rapid prototyping to a specific resolution offers a much less expensive alternative with increased throughput due to the speed of current rapid prototyping systems.