title: Covalent attachment of mechanoresponsive luminescent micelles to glasses and polymers in aqueous conditions.
abstract: Covalent attachment of mechanoresponsive luminescent organic or organometallic compounds to other materials is a promising approach to develop a wide variety of mechanoresponsive luminescent materials. Here, we report covalently linkable mechanoresponsive micelles that change their photoluminescence from yellow to green in response to mechanical stimulation under aqueous conditions. These micelles are composed of a dumbbell-shaped amphiphilic pyrene derivative having amine groups at the peripheral positions of its dendrons. Using a well-established cross-linker, the micelles were covalently linked via their peripheral amine groups to the surface of glass beads, polylactic acid (PLA) beads, and living cells under aqueous conditions. Vortexing of glass beads bearing the micelles in a glass vial filled with water caused a photoluminescence color change from yellow to green. PLA beads bearing the micelles showed no change in photoluminescence color under the same conditions. We ascribe this result to the lower density and stiffness of the PLA beads, because the color of the PLA beads changed on vortexing in the presence of bare glass beads. HeLa cells and HL-60 cells bearing the micelles showed no obvious photoluminescence color change under vortexing. The structure, photophysical properties, and mechanism of photoluminescence color change of the micellar assemblies were examined.
authors.affiliation: Graduate School of Pharmaceutical Sciences, The University of Tokyo , 7-3-1, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
authors.forename: Yoshimitsu
authors.initials: Y
authors.lastname: Sagara
authors.forename: Toru
authors.initials: T
authors.lastname: Komatsu
authors.forename: Tasuku
authors.initials: T
authors.lastname: Ueno
authors.forename: Kenjiro
authors.initials: K
authors.lastname: Hanaoka
authors.forename: Takashi
authors.initials: T
authors.lastname: Kato
authors.forename: Tetsuo
authors.initials: T
authors.lastname: Nagano
mesh_terms: D005898:Glass / Q000737:chemistry*; D018922:HL-60 Cells; D006801:Humans; D019344:Lactic Acid / Q000737:chemistry*; D049449:Luminescence; D008823:Micelles; D010316:Particle Size; D011091:Polyesters; D011108:Polymers / Q000737:chemistry*; D011721:Pyrenes / Q000138:chemical synthesis / Q000737:chemistry*; D013499:Surface Properties; D013501:Surface-Active Agents / Q000138:chemical synthesis / Q000737:chemistry*; D014867:Water / Q000737:chemistry
chemical_list: D008823:Micelles; D011091:Polyesters; D011108:Polymers; D011721:Pyrenes; D013501:Surface-Active Agents; D014867:Water; D019344:Lactic Acid; C033616:poly(lactide); C030984:pyrene