Transparent Protein Microtubule Motors with Controllable Velocity and Biodegradability

Slender protein microtube motors with a catalase interior surface are self-propelled in aqueous H2O2 by jetting O2 microbubbles from the open-end terminus. Immobilization of a catalase biocatalyst on the internal wall is achieved using avidin–biotin complexation. It is particularly interesting that the migration of O2 bubbles in the 1D channel and their subsequent expulsions were clearly visible because the tube walls are transparent. The microtube motor velocity reached a maximum at the optimum pH and temperature of the catalase. Furthermore, the microtubes were digested completely by proteases, showing sufficient biodegradability