Three-dimensional microfabrication system toward advanced biodegradable implantable devices

We have developed a novel three-dimensional microfabrication method for biodegradable polymers. Unlike conventional processes, our process satisfies high-resolution and highspeed requirements. The system design allows us the processing of micro-level forms by stacking up melted polymers from the nozzle. 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 /spl mu/m and 45 /spl mu/n, respectively. Biodegradable polymers enable three-dimensional microstructures such as micro-pipes, micro-bends, and micro-coil springs to be manufactured in less than 15 min. The biocompatibility of the structure was evaluated using a cell line (PC12). A small vessel, with a transparent base, was fabricated using PLA and cells were cultivated in it. The cell morphology and the proliferation were then compared with the results obtained using the standard method. Our system renders it possible to produce toxic-free, and leakage-free devices. The mechanical strength of our microstructures was evaluated using a tensile strength test. The tensile strength of the microstructure was lower than the one obtained from the conventional method, but has enough strength for fabrication of medical devices. Our system is expected to have potential applications in optimum design and fabrication of implantable devices.