Real three-dimensional microfabrication for biodegradable polymers: demonstration of high-resolution and biocompatibility for implantable microdevices

We have developed a novel three-dimensional (3D) microfabrication method for biodegradable polymers. Unlike conventional processes, our process satisfies high-resolution and high-speed requirements. The system design allows us the processing of microlevel forms by stacking up melted polymers from the nozzle. We adopted a batch process to supply materials in order to eliminate the prior process that required toxic solvents. In addition, it is possible to handle almost all biodegradable thermoplastic resins by adopting this system. A single layer from the piled-up layers of extruded lines was observed to evaluate the resolution. The lateral and depth resolutions attained are 40 μm and 45 μm, respectively. Biodegradable polymers enable three-dimensional microstructures such as micropipes, microbends, and microcoil springs to be manufactured in less than 15 min. The biocompatibility of the newly fabricated structure was evaluated using a cell line (PC12). For this purpose, a small vessel, with a transparent base, was fabricated using PLA and cells were cultivated in it. The results were then compared with the results obtained using the standard method. Our system renders it possible to produce toxic-free, as well as transparent and leakage-free devices. Our system is expected to have potential applications in optimum design and fabrication of implantable devices, especially in tissue engineering.