title: Light-driven directed motion of azobenzene-coated polymer nanoparticles in an aqueous medium.
abstract: Azobenzene-coated polymer nanoparticles in the 16-nm-diameter range act as phototriggered nanomotors combining photo to kinetic energy conversion with optical control through light intensity gradients. The grafted dyes act as molecular propellers: their photoisomerization supplies sufficient mechanical work to propel the particles in an aqueous medium toward the intensity minima with velocities of up to 15 μm/s. It is shown that nanoparticles can be driven over tens of micrometers by translating the intensity gradients in the plane. The analysis of the particles motion demonstrates the decisive role of photoisomerization in the transport with a measured driving force that is 3 to 4 orders of magnitude higher than optical forces.
authors.affiliation: Institut d'Alembert, Laboratoire de Photonique Quantique et Moléculaire, Ecole Normale Supérieure de Cachan, 61 Avenue du Président Wilson, 94235 Cachan, France.
authors.forename: Jean-Pierre
authors.initials: JP
authors.lastname: Abid
authors.forename: Michel
authors.initials: M
authors.lastname: Frigoli
authors.forename: Robert
authors.initials: R
authors.lastname: Pansu
authors.forename: Jacob
authors.initials: J
authors.lastname: Szeftel
authors.forename: Joseph
authors.initials: J
authors.lastname: Zyss
authors.forename: Chantal
authors.initials: C
authors.lastname: Larpent
authors.forename: Sophie
authors.initials: S
authors.lastname: Brasselet
mesh_terms: D001391:Azo Compounds / Q000737:chemistry* / Q000528:radiation effects; D007700:Kinetics; D008027:Light; D015394:Molecular Structure; D009038:Motion; D053758:Nanoparticles / Q000737:chemistry* / Q000528:radiation effects*; D010316:Particle Size; D011108:Polymers / Q000737:chemistry* / Q000528:radiation effects; D013499:Surface Properties; D014867:Water / Q000737:chemistry*
chemical_list: D001391:Azo Compounds; D011108:Polymers; D014867:Water; C009850:azobenzene