Solvent response of polymers for micromachine manipulation.

A novel solvent responsive polymer micromachine has been successfully fabricated by two-photon photopolymerization (TPP) of methacrylate-based photoresists. The moving part of the micromachine could be easily driven by interfacial solvent polarity induced swelling and shrinking of the photopolymer networks. Furthermore, the driving performance of the micromachine could be precisely modulated by varying the laser scanning step length during fabrication.