Micro-fabrication of biodegradable plastic
Development of micro-/nano-fabrication technology of PLLA
n the advanced medical field, various kind of medical devices, such as lab-on-a-chip which can diagnose disease by one drop of blood and micro-machine embedded in our body for health check, has been developed through the use of the precise fabrication technique. For the development of these medical devices, development of micro-/nano-fabrication technology and functionalization of a biocompatible material, for example, cell adhesion control, are important. PLLA is highly biocompatible and has been used as implants and sutures.In our research project, the film of PLLA is fabricated in micro-/nano-meter region by using 30 keV Ga focused ion beam with 50 nm or less diameter. PLLA film is easily thermally deformed at above glass transition temperature (about 60 ℃), however, any structures, for example, 60 nm groove, 80 nm holes, characters and so on, can be fabricated by optimizing the irradiation and preparation conditions. Furthermore, the bottom surface drilled by irradiation is changed to the diamond-like carbon with increasing in C = C double bond. Since the strength of the cell adhesiveness is controlled by the amount of C = C on the DLC surface, the obtained fine structural PLLA would be applied for the bio-devices that can regulate cell adhesion locally.
