Amphiphilic nanostructure in choline carboxylate and amino acid ionic liquids and solutions

Abstract

The liquid structures of six choline carboxylate/amino acid ionic liquids (bio-ILs) and their mixtures with water and various n-alkanols have been investigated by small-angle X-ray scattering (SAXS).

Exploring conformational preferences of proteins: ionic liquid effects on the energy landscape of avidin

“…29,30 This is consistent for all of the ILs examined, apart from [Cho][Hex], which showed a strong background signal in the SAXS measurement at 50 wt%, attributed to a combination of the high hydrophobicity of [Cho][Hex] relative to the other ILs and the high IL content used, as previously observed in aqueous solution of the IL choline iso-butyrate. 31 Furthermore, despite the high, potentially denaturing pH of the [Cho][Phe] and [Cho] [Met] environments, the R g value of unmodied avidin decreased (albeit higher initial R g values) with increasing concentration. This consistent trend could suggest a conformational shi from conformer of higher conformational exibility to compact conformers, and preferences that restrict the conformational search by chain compaction.…”

Perspectives in the Computational Modeling of New Generation, Biocompatible Ionic Liquids

“…ILs, in general, show a rather complicated pattern of structural features at the nanoscopic scale. 30 This includes segregation phenomena, 31 − 33 self-assembly, 34 , 35 and unusual HB networks. 36 − 42 PILs, in particular, are characterized by the existence of a pervasive network of hydrogen bonds (HBs) that makes them unique in the vast population of possible ILs.…”

“…In PILs the network of HBs represents an additional source of disorder and the formation of segregated apolar domains is often suppressed (for peculiar cases see refs ( 34 and 35 )). However, even in the presence of conspicuous HBs, the formation of peculiar structures is not impossible.…”

Cholinium amino acid-based ionic liquids

“…These experiments show that molecular segregation is present, as well as the existence of anion-rich domains which are controlled by inter-anion hydrogen bonds. These anionic aggregation phenomena might also be responsible for the low-Q correlations spotted in SAXS diffraction patterns which are otherwise difficult to attribute to more common effects such as apolar domain segregation in compounds which do not have long aliphatic chains (Miao et al 2020a).…”