Ultrafast twisting dynamics of thioflavin-T: spectroscopy of the twisted intramolecular charge-transfer state.

Abstract

Understanding the excited-state properties of thioflavin-T (ThT) has been of immense importance, because of its efficient amyloid-sensing ability related to neurodegenerative disorders. The excited-state dynamics of ThT is studied by using sub-pico- and nanosecond time-resolved transient absorption techniques as well as density functional theory (DFT)/time-dependent DFT calculations. Barrierless twisting around the central C-C bond between two aromatic moieties is the dominant process that contributes to the ultrafast dynamics of the S1 state. The spectroscopic properties of the intramolecular charge-transfer state are characterized for the first time. The energetics of the S0 and S1 states has also been correlated with the experimentally observed spectroscopic parameters and structural dynamics. A longer-lived transient state populated with a very low yield has been characterized as the triplet state.

• Authors: Rajib Ghosh, Dipak K Palit
• Journal: Chemphyschem : a European journal of chemical physics and physical chemistry (Chemphyschem) Vol. 15 Issue 18 Pg. 4126-31 (Dec 15 2014) ISSN: 1439-7641 [Electronic] Germany
• PMID: 25251013 (Publication Type: Journal Article)
• Copyright: © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Chemical References

• Benzothiazoles
• Fluorescent Dyes
• Thiazoles
• thioflavin T

Topics

• Benzothiazoles
• Fluorescent Dyes (chemistry)
• Models, Molecular
• Quantum Theory
• Spectrometry, Fluorescence
• Thiazoles (chemistry)
• Time Factors