TY - JOUR
T1 - Thermodynamic factors impacting the peptide-driven self-assembly of perylene diimide nanofibers
AU - Eakins, Galen L.
AU - Gallaher, Joseph K.
AU - Keyzers, Robert A.
AU - Falber, Alexander
AU - Webb, James E.A.
AU - Laos, Alistair
AU - Tidhar, Yaron
AU - Weissman, Haim
AU - Rybtchinski, Boris
AU - Thordarson, Pall
AU - Hodgkiss, Justin M.
N1 - Copyright:
Copyright 2014 Elsevier B.V., All rights reserved.
PY - 2014/7/24
Y1 - 2014/7/24
N2 - Synthetic peptides offer enormous potential to encode the assembly of molecular electronic components, provided that the complex range of interactions is distilled into simple design rules. Here, we report a spectroscopic investigation of aggregation in an extensive series of peptide-perylene diiimide conjugates designed to interrogate the effect of structural variations. By fitting different contributions to temperature dependent optical absorption spectra, we quantify both the thermodynamics and the nature of aggregation for peptides by incrementally varying hydrophobicity, charge density, length, as well as asymmetric substitution with a hexyl chain, and stereocenter inversion. We find that coarse effects like hydrophobicity and hexyl substitution have the greatest impact on aggregation thermodynamics, which are separated into enthalpic and entropic contributions. Moreover, significant peptide packing effects are resolved via stereocenter inversion studies, particularly when examining the nature of aggregates formed and the coupling between π electronic orbitals. Our results develop a quantitative framework for establishing structure-function relationships that will underpin the design of self-assembling peptide electronic materials.
AB - Synthetic peptides offer enormous potential to encode the assembly of molecular electronic components, provided that the complex range of interactions is distilled into simple design rules. Here, we report a spectroscopic investigation of aggregation in an extensive series of peptide-perylene diiimide conjugates designed to interrogate the effect of structural variations. By fitting different contributions to temperature dependent optical absorption spectra, we quantify both the thermodynamics and the nature of aggregation for peptides by incrementally varying hydrophobicity, charge density, length, as well as asymmetric substitution with a hexyl chain, and stereocenter inversion. We find that coarse effects like hydrophobicity and hexyl substitution have the greatest impact on aggregation thermodynamics, which are separated into enthalpic and entropic contributions. Moreover, significant peptide packing effects are resolved via stereocenter inversion studies, particularly when examining the nature of aggregates formed and the coupling between π electronic orbitals. Our results develop a quantitative framework for establishing structure-function relationships that will underpin the design of self-assembling peptide electronic materials.
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U2 - 10.1021/jp504564s
DO - 10.1021/jp504564s
M3 - Article
C2 - 24950450
AN - SCOPUS:84905020682
VL - 118
SP - 8642
EP - 8651
JO - Journal of Physical Chemistry B
JF - Journal of Physical Chemistry B
SN - 1520-6106
IS - 29
ER -