Fabrication Of Multi-component Micromotors

Inspired by the molecular motors in nature that can efficiently and autonomously perform tasks in organisms,the research about fabrication of artificial micromotors has received extensive attention in recent years and the micromotors are expected to be applied to different fields with various scales.Up to now,a variety of methods,such as electrochemical deposition,surface asymmetric modification and 3D printing,have been successfully developed to fabricate micromotors with various shapes like linear,tubular and spherical.However,most of the existing fabrication methods are cumbersome and extremely time-consuming,making it difficult to achieve mass production in a short time.In addition,there have not been a simple method to put more functions on micromotors to expand their application fields.Since these negative factors have greatly limited the development speed of micromotors,there is an urgent need to research for a simple new method to fabricate multifunctional micromotors.Microfluidic technology is a technical application to accurately control and operate micro fluids on a micro scale.This emerging technology is widely used in the fabrication of various droplets with complex structures relied on its own advantages such as high accuracy and ease of operation.Since this technology can produce a large number of droplets with excellent monodispersity and highly controllable structure or component in a short time through continuous emulsification,we choose to combine the microfluidic technology with micromotor fabrication in this paper and innovatively develop a new microfluidic emulsification method to quickly fabricate two shapes of multi-component micromotors,and explore their various applications at the micro-and macro-levels.The specific research works are as follows:(1)Fabrication of multi-component spherical micromotors: Use capillary microfluidic technology to generate double emulsion droplet templates,and then incorporate different functional nanoparticles respectively into the dual internal phase solutions,and next precisely adjust the flow rate of each phase solution to obtain multi-component spherical micromotors with optimal parameters and good monodispersity under ultraviolet(UV),and finally use various characterization methods to characterize the structures and components of micromotors.(2)Fabrication of multi-component peanut-shaped micromotors: Construct a coaxial capillary microfluidic system with emulsification and textile capabilities to generate emulsion droplets wrapped in fibers,and then blend different functional nanoparticles in the internal phase solutions and accurately tune the flow rate of each phase solution according to the experimental requirements,and finally utilize the appropriate stretching of the external elastic fibers to fabricate multi-component peanut-shaped micromotors with excellent monodispersity and characterize their internal and external microstructures.(3)Research on the micro-and macro-applications of multi-component micromotors:Combining the self-propelling ability conferred by platinum(Pt)nanoparticles with the magnetic guidance ability conferred by magnetic nanoparticles,the directional delivery of spherical micromotors and the directional stirring of peanut-shaped micromotors were realized on micro-applications.Then combine a large number of micromotors with macroadsorbed object and control the motion state of the macro-object by micromotors,and realize the directional delivery and sewage purification of micromotors on macro-applications.