title: Biohybrid Microtube Swimmers Driven by Single Captured Bacteria.
abstract: Bacteria biohybrids employ the motility and power of swimming bacteria to carry and maneuver microscale particles. They have the potential to perform microdrug and cargo delivery in vivo, but have been limited by poor design, reduced swimming capabilities, and impeded functionality. To address these challenge, motile Escherichia coli are captured inside electropolymerized microtubes, exhibiting the first report of a bacteria microswimmer that does not utilize a spherical particle chassis. Single bacterium becomes partially trapped within the tube and becomes a bioengine to push the microtube though biological media. Microtubes are modified with "smart" material properties for motion control, including a bacteria-attractant polydopamine inner layer, addition of magnetic components for external guidance, and a biochemical kill trigger to cease bacterium swimming on demand. Swimming dynamics of the bacteria biohybrid are quantified by comparing "length of protrusion" of bacteria from the microtubes with respect to changes in angular autocorrelation and swimmer mean squared displacement. The multifunctional microtubular swimmers present a new generation of biocompatible micromotors toward future microbiorobots and minimally invasive medical applications.
authors.affiliation: Lab-in-a-Tube and Nanorobotic Biosensors, Max Planck Institute for Intelligent Systems, Heisenbergstraße 3, 70569, Stuttgart, Germany.
authors.forename: Morgan M
authors.initials: MM
authors.lastname: Stanton
authors.affiliation: Physical Intelligence, Max Planck Institute for Intelligent Systems, Stuttgart, 70569, Germany.
authors.forename: Byung-Wook
authors.initials: BW
authors.lastname: Park
authors.affiliation: Smart Nano-Bio-Devices, Institut de Bioenginyeria de Catalunya (IBEC), 08028, Barcelona, Spain.
authors.forename: Albert
authors.initials: A
authors.lastname: Miguel-López
authors.affiliation: Lab-in-a-Tube and Nanorobotic Biosensors, Max Planck Institute for Intelligent Systems, Heisenbergstraße 3, 70569, Stuttgart, Germany.|School of Materials Science and Engineering, Harbin Institute of Technology Shenzhen Graduate School, 518055, Shenzhen, China.
authors.forename: Xing
authors.initials: X
authors.lastname: Ma
authors.affiliation: Physical Intelligence, Max Planck Institute for Intelligent Systems, Stuttgart, 70569, Germany.
authors.forename: Metin
authors.initials: M
authors.lastname: Sitti
authors.affiliation: Lab-in-a-Tube and Nanorobotic Biosensors, Max Planck Institute for Intelligent Systems, Heisenbergstraße 3, 70569, Stuttgart, Germany.|Smart Nano-Bio-Devices, Institut de Bioenginyeria de Catalunya (IBEC), 08028, Barcelona, Spain.|Institució Catalana de Recerca i EstudisAvancats (ICREA), Pg. Lluís Companys 23, 08010, Barcelona, Spain.
authors.forename: Samuel
authors.initials: S
authors.lastname: Sánchez
mesh_terms: D001419:Bacteria / Q000235:genetics*; D004926:Escherichia coli / Q000235:genetics; D007211:Indoles / Q000737:chemistry; D011108:Polymers / Q000737:chemistry; D013550:Swimming
chemical_list: D007211:Indoles; D011108:Polymers; C568283:polydopamine
keywords: E. coli; biohybrids; micromotors; microswimmers; polydopamine