Layer-by-layer Assembly And Propulsion Mechanism Of Polymer Multilayer Rockets

In nature, the enzyme protein molecules ins ide live cells relies on the catalyt ic decomposit ion of ATP to complete intracellular transport, DN A replication, cell division and differentiation, even muscle contraction. It inspires scientists to mimic these natural biological molecular motors, designing and fabricating micro and nano scale device that responds to external physical or chemical stimuli and convert it to rotate, shrink, shuttle or other mechanical movement, namely man- made micro/nano- motors. Artificial micro/nano motor is one o f the most popular topic of today’s micro/nano technology. It has great potential in biomedical, sensing, environmental monitoring and food safety fields. However, the preparation of man- made micro/nano motor is complex and expensive. And the motor could hardly be modified. Thus limite application of the artificia l motor in many fields.This artical design new polyelectrolyte artificial microrocket motor system through combine layer-by- layer assembly and template technology. Due to advantages combinated of layer by layer assembly and template technology,this new synthetic polyelectrolyte micro rocket motor simultaneously have composition and size controllablity, good biocompatible and biodegradable and so on. O ur research covers the following two aspects:Assembly and movement behavior of bubble propelled rockets in different media: prepared platinum modified polye lectrolyte multilayers micro- rockets by layer-by- layer assembly, and characterize the rockets’ morphology by optical microscopy,scanning electron microscopy and transmission electron microscopy. In the environment of deionized water, seawater and serum,micro-rocjets’ velocity range from 50 μm/s to 980 μm/s. Also we observe the micro-bubble generating in rocket’s cavity and forward/backward movement of micro-rockets, and we explain the bubble propellde mechanis m.Cancer cells direction selective recognization of near- infrared laser driving micro rockets: we designed and fabricated gold and hyaluronic acid modified micro-rockets, and characterize rockets’ morphology by the optical microscopy and scanning electron microscopy.Under near- infrared laser irradiation, micro- rocket can be propelled, the maximum speed reach 500 μm/s. Experiments show that near- infrared laser driven of rockets repeat well. Also we achieve adirection selectively recognit ion of micro-rockets for human cancer cells.