title: Ultrafast structural dynamics of the photocleavage of protein hybrid nanoparticles.
abstract: Protein-coated gold nanoparticles in suspension are excited by intense laser pulses to mimic the light-induced effect on biomolecules that occur in photothermal laser therapy with nanoparticles as photosensitizer. Ultrafast X-ray scattering employed to access the nanoscale structural modifications of the protein-nanoparticle hybrid reveals that the protein shell is expelled as a whole without denaturation at a laser fluence that coincides with the bubble formation threshold. In this ultrafast heating mediated by the nanoparticles, time-resolved scattering data show that proteins are not denatured in terms of secondary structure even at much higher temperatures than the static thermal denaturation temperature, probably because time is too short for the proteins to unfold and the temperature stimulus has vanished before this motion sets in. Consequently the laser pulse length has a strong influence on whether the end result is the ligand detachment (for example drug delivery) or biomaterial degradation.
authors.affiliation: Institute for Synchrotron Radiation, Karlsruhe Institute of Technology, Postfach 3640, D-76021 Karlsruhe, EU.
authors.forename: Shyjumon
authors.initials: S
authors.lastname: Ibrahimkutty
authors.forename: Jangbae
authors.initials: J
authors.lastname: Kim
authors.forename: Marco
authors.initials: M
authors.lastname: Cammarata
authors.forename: Friederike
authors.initials: F
authors.lastname: Ewald
authors.forename: Jungkweon
authors.initials: J
authors.lastname: Choi
authors.forename: Hyotcherl
authors.initials: H
authors.lastname: Ihee
authors.forename: Anton
authors.initials: A
authors.lastname: Plech
mesh_terms: D008027:Light; D008422:Materials Testing; D049329:Nanostructures / Q000737:chemistry* / Q000528:radiation effects* / Q000648:ultrastructure; D011485:Protein Binding / Q000528:radiation effects; D011487:Protein Conformation / Q000528:radiation effects; D011506:Proteins / Q000737:chemistry* / Q000528:radiation effects*
chemical_list: D011506:Proteins