title: Motion-based, high-yielding, and fast separation of different charged organics in water.
abstract: We report a self-propelled Janus silica micromotor as a motion-based analytical method for achieving fast target separation of polyelectrolyte microcapsules, enriching different charged organics with low molecular weights in water. The self-propelled Janus silica micromotor catalytically decomposes a hydrogen peroxide fuel and moves along the direction of the catalyst face at a speed of 126.3 μm s(-1) . Biotin-functionalized Janus micromotors can specifically capture and rapidly transport streptavidin-modified polyelectrolyte multilayer capsules, which could effectively enrich and separate different charged organics in water. The interior of the polyelectrolyte multilayer microcapsules were filled with a strong charged polyelectrolyte, and thus a Donnan equilibrium is favorable between the inner solution within the capsules and the bulk solution to entrap oppositely charged organics in water. The integration of these self-propelled Janus silica micromotors and polyelectrolyte multilayer capsules into a lab-on-chip device that enables the separation and analysis of charged organics could be attractive for a diverse range of applications.
authors.affiliation: State Key Lab of Urban Water Resource and Environment, Micro/Nanotechnology Research Centre, Harbin Institute of Technology, Harbin 150080 (PR China).
authors.forename: Mingjun
authors.initials: M
authors.lastname: Xuan
authors.forename: Xiankun
authors.initials: X
authors.lastname: Lin
authors.forename: Jingxin
authors.initials: J
authors.lastname: Shao
authors.forename: Luru
authors.initials: L
authors.lastname: Dai
authors.forename: Qiang
authors.initials: Q
authors.lastname: He
mesh_terms: D001710:Biotin / Q000737:chemistry; D002214:Capsules / Q000737:chemistry; D002384:Catalysis; D004396:Coloring Agents / Q000302:isolation & purification*; D004573:Electrolytes / Q000737:chemistry; D004867:Equipment Design; D006861:Hydrogen Peroxide / Q000737:chemistry; D046210:Microfluidic Analytical Techniques / Q000295:instrumentation*; D009038:Motion; D012822:Silicon Dioxide / Q000737:chemistry; D019809:Streptavidin / Q000737:chemistry; D014867:Water / Q000032:analysis*
chemical_list: D002214:Capsules; D004396:Coloring Agents; D004573:Electrolytes; D014867:Water; D001710:Biotin; D012822:Silicon Dioxide; D019809:Streptavidin; D006861:Hydrogen Peroxide
keywords: Janus micromotors; capsules; dyes/pigments; microfluidic chip; silicon