Vibrational Energy Transport through a Capping Layer of Appropriately Designed Peptide Helices over Gold Nanoparticles

Physikalisch-Chemisches Institut, Universität Zürich, CH-8057 Zürich, Switzerland.
Nano Letters (Impact Factor: 13.59). 08/2010; 10(8):3057-61. DOI: 10.1021/nl101580w
Source: PubMed


We design and characterize spherical gold nanoparticles, which are covalently linked to and completely covered by
3(10)-helical peptides. These helices provide a scaffold to place C-13=O isotope labels at defined distances from the gold surface, which we employ as local thermometers. Probing
these reporter groups with transient infrared spectroscopy, we monitor the vibrational energy flow across the peptide capping layer following excitation of the nanoparticle plasmon resonance.

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    • "Nevertheless, as shown by Leitner and coworkers, localized highfrequency modes preferably couple to other localized modes that overlap in space, while the anharmonic coupling between a localized and a delocalized mode is typically very small [39]. Therefore, one can assume that the local C=O thermometer in our experiments [19] [20] [21] [22] tentatively overestimates the contribution of other localized parking modes and does not sufficiently account for the energy in the delocalized transporting modes. In such a scenario, the measured apparent heat diffusivity is dominated by localized modes that receive vibrational energy delayed through intra-site "
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