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Amplification of Electronic Circular Dichroism-A Tool to Follow Self-Assembly of Chiral Molecular Capsules.

ABSTRACT: Electronic circular dichroism (ECD) can be used to study various aspects of self-assembly (definition of stoichiometric ratios, chirality amplification during self-assembly, host-guest complexation). In this work, we show that ECD is a valuable tool for monitoring the self-assembly of chiral peptide-based capsules. By analyzing the signs, intensities, and temperature dependences of ECD bands, the effects of the non-specific processes can be separated from the restriction of intramolecular motion (RIM) caused by discrete self-assembly. Analysis of experimental and theoretical ECD spectra show that the differences between assembled and non-assembled species originate from induction of inherently chiral conformation and restriction of conformational freedom that leads to amplification of ECD signals during self-assembly of discrete species.

SUBMITTER: Szymanski MP

PROVIDER: S-EPMC8658961 | biostudies-literature | 2021 Nov

REPOSITORIES: biostudies-literature

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Amplification of Electronic Circular Dichroism-A Tool to Follow Self-Assembly of Chiral Molecular Capsules.

Szymański Marek P MP Grajda Marcin M Szumna Agnieszka A

Molecules (Basel, Switzerland) 20211124 23

Electronic circular dichroism (ECD) can be used to study various aspects of self-assembly (definition of stoichiometric ratios, chirality amplification during self-assembly, host-guest complexation). In this work, we show that ECD is a valuable tool for monitoring the self-assembly of chiral peptide-based capsules. By analyzing the signs, intensities, and temperature dependences of ECD bands, the effects of the non-specific processes can be separated from the restriction of intramolecular motion ...[more]

PMID: 34885682

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