posted on 2024-01-19, 14:03authored byMeiqi Li, Aoli Wu, Lian Li, Zibo Li, Hengchang Zang
The exploration of short peptide-based assembly is vital
for understanding
protein-misfolding-associated diseases and seeking strategies to attenuate
aggregate formation. While, the molecular mechanism of their structural
evolution remains poorly studied in view of the dynamic and unpredictable
assembly process. Herein, infrared (IR) spectroscopy, which serves
as an in situ and real-time analytical technique, was intelligently
employed to investigate the mechanism of phase transition and aggregate
formation during the dynamic assembly process of diphenylalanine.
Combined with other spectroscopy and electron microscopy technologies,
three stages of gel formation and the main driving forces in different
stages were revealed. A variety of stoichiometric methods such as
continuous wavelet transform, principal component analysis, and two-dimensional
correlation spectroscopy techniques were conducted to analyze the
original time-dependent IR spectra to obtain detailed information
on the changes in the amide bands and hydration layer. The microenvironment
of hydrogen bonding among amide bands was significantly changed with
the addition of pyridine derivatives, resulting in great differences
in the properties of co-assembled gels. This work not only provides
a universal analytical way to reveal the dynamic assembly process
of dipeptide-based supramolecular gel but also expands their applications
in supramolecular regulation and high-throughput screens in situ.