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Polymers and Self Assembly: From Biology to Nanomaterials Poster Session I
44-POS
Board 44
Material Characterization of Ultra-Short Peptides at Low and High Concentrations in
Water
Christophe Tarabout
1
, Carmen Valverde Tercedor
1
, Stephan Jokisch
2
, Luca Bertinetti
1
,
Damien Faivre
1
.
1
Max planck institut for colloids and interfaces, Potsdam, Germany,
2
Universität Bayreuth,
Bayreuth, Germany.
Ultra-short peptides can be used for systematic mutation studies because of their simplicity and
low cost. Understanding their self-assembly is important for controlling the growth of the
structures and creating new biomaterials. Recently, a few teams have used bioinformatic
methods to predict their potential for aggregation.
We have taken the opposite approach and characterized a family of related short peptides from a
material science point of view. For peptides at low concentrations in water, we observe in
rheometry experiments that small changes in the sequence can modify the behavior from shear
thinning to shear thickening. For peptides at high concentration, amorphous solids and fibers
were studied using DSC, mechanical testing, X-ray diffraction and SEM. For some sequences,
with the right amount of water, the materials could exhibit self-healing capacity. We will also
report how replacement of counterions, modification of charge, size, aromaticity/aliphaticity,
hydrophilicity/hydrophobicity and order of the aminoacid sequence affect the macroscopic
material properties. The most noticeable effects are the material resistance to heating and
propensity to absorb humidity. This study is a necessary step to understand and tune the
properties of small peptides as new materials.