A Lyotropic Liquid Crystal from a Flexible Oligopeptide Amphiphile in Dimethyl Sulfoxide

Abstract

Despite the rapid progress in peptide liquid crystals (LCs) due to their prominent properties, our investigation on flexible peptide-based LCs is incomplete, mainly resulted from their unclear formation mechanisms and unexploited applications in organic solvents. Here, we develop a lyotropic LC based on a flexible oligopeptide amphiphile, which aggregates into aligned cylinder-like nanostructures in dimethyl sulfoxide (DMSO). The formation mechanism of lyotropic LC in DMSO was probed by the experimental investigation and molecular dynamics simulation, indicating that the hydrogen bonding and hydrophobic and electrostatic interactions contribute to the formation of ordered nanostructures in the organic solvent. Arising from the orientational order and suitable fluidity, we exploit the application of lyotropic LC as an aligned medium to measure the residual dipolar couplings of bioactive molecules. This study not only offers the understanding of the mechanism to create LC systems without rigid aromatic groups but also expands the applications of ordered bottom-up nanomaterials in organic solvents.

Self‐Assembly of Helical Polymers and Oligomers to Create Liquid Crystalline Alignment for Anisotropic NMR Parameters

“…To build functional LC systems, Lei et al have developed a novel strategy referring to supramolecular self-assembly of lowmolecular-weight units into ordered nanostructures in order to align the analytes (Figure 9). [62][63][64][65][66][67] Furthermore, the oligopeptides can be prepared easily through the solid-phase peptide synthesis (SPPS) on large scale. Their robust self-assembly propensity, which involves non-covalent interactions and shear action, provides a great opportunity for alignment media formation.…”

“…Furthermore, the concentration‐dependent orientation in LC was confirmed by 2D SAXS. [ 66 ] These properties combined with the suitable fluidity of self‐assembled lyotropic LC show the great potential of acting as an ideal aligned medium to measure RDCs of molecules.…”

“…To investigate the applicability of self-assembled C 15 H 31 -CONH-A 5 KE 2 -CONH 2 LC as an aligned medium for RDC acquisition, here, by way of illustration, the aromatic estrone was [66] Copyright 2020, American Chemical Society. [66] Copyright 2020, American Chemical Society.…”

“…To investigate the applicability of self-assembled C 15 H 31 -CONH-A 5 KE 2 -CONH 2 LC as an aligned medium for RDC acquisition, here, by way of illustration, the aromatic estrone was [66] Copyright 2020, American Chemical Society. [66] Copyright 2020, American Chemical Society. employed as the model molecule, the F 1 -coupled J-scaled BIRD-HSQC (JSB-HSQC) spectrum of estrone was first recorded in this anisotropic medium, and the isotropic DMSO-d 6 was used as control.…”

“…b) Correlations between the experimental and back-calculated 1 D CH values using the DFT-optimized structure of estrone as the input, The Q factor is 0.079. c) The detailed assignments information and their RDCs values of estrone. Reproduced with permission [66]. Copyright 2020, American Chemical Society.…”