09:45 〜 10:00
▼ [8a-A502-4] Fabrication of 3D Proteinaceous Microstructures by Femtosecond Laser Direct Writing: Reduction of Water Fraction to Hinder Cavitation Bubble Formation
キーワード：photoinduced, cross-linking, protein
We discuss two strategies to reduce water fraction in aqueous systems usually required for microfabrication of proteinaceous structures by femtosecond (fs) laser direct writing (LDW). Microstructures made of protein have been created using a two-photon polymerization technique with fs LDW by photoinduced cross-linking of proteins. Protein cross-linking can be induced when the laser intensity exceeds two-photon absorption threshold as well as the incident dose exceeds the polymerization threshold, while the higher laser intensity tends to generate cavitation bubbles. Cavitation bubbles are formed when laser-induced heat leads to expansion of the aqueous medium, as a common aspect in other laser-derived technologies. Depending on the size of the formed bubble, damage to already fabricated structures or strong light scattering hinders the fabrication process. Here, we alter protein solution constituents to reduce the water fraction and notably even fabricate proteinaceous structures without water fraction by using a gently dried drop-cast solution.