Distinct Electrostatic Interactions Govern the Chiro-Optical Properties and Architectural Arrangement of Peptide–Oligothiophene Hybrid Materials

The development of chiral optoelectronic materials is of great interest due to their potential of being utilized in electronic devices, biosensors, and artificial enzymes. Herein, we report the chiral–optical properties and architectural arrangement of optoelectronic materials generated from noncovalent self-assembly of a cationic synthetic peptide and five chemically defined anionic pentameric oligothiophenes. The peptide–oligothiophene hybrid materials exhibit a three-dimensional ordered helical structure and optical activity in the π–π* transition region that are observed due to a single chain induced chirality of the conjugated thiophene backbone upon interaction with the peptide. The latter property is highly dependent on electrostatic interactions between the peptide and the oligothiophene, verifying that a distinct spacing of the carboxyl groups along the thiophene backbone is a major chemical determinant for having a hybrid material with distinct optoelectronic properties. The necessity of the electrostatic interaction between specific carboxyl functionalities along the thiophene backbone and the lysine residues of the peptide, as well as the induced circular dichroism of the thiophene backbone, was also confirmed by theoretical calculations. We foresee that our findings will aid in designing optoelectronic materials with dynamic architectonical precisions as well as offer the possibility to create the next generation of materials for organic electronics and organic bioelectronics

Evidence for Age-Dependent <i>in Vivo</i> Conformational Rearrangement within Aβ Amyloid Deposits

Deposition of aggregated Aβ peptide in the brain is one of the major hallmarks of Alzheimer’s disease. Using a combination of two structurally different, but related, hypersensitive fluorescent amyloid markers, LCOs, reporting on separate ultrastructural elements, we show that conformational rearrangement occurs within Aβ plaques of transgenic mouse models as the animals age. This important mechanistic insight should aid the design and evaluation of experiments currently using plaque load as readout

Evidence for Age-Dependent <i>in Vivo</i> Conformational Rearrangement within Aβ Amyloid Deposits

Deposition of aggregated Aβ peptide in the brain is one of the major hallmarks of Alzheimer’s disease. Using a combination of two structurally different, but related, hypersensitive fluorescent amyloid markers, LCOs, reporting on separate ultrastructural elements, we show that conformational rearrangement occurs within Aβ plaques of transgenic mouse models as the animals age. This important mechanistic insight should aid the design and evaluation of experiments currently using plaque load as readout