Studies on supramolecular gel aggregates via supramolecular interactions are very fascinating and impressive. The interactions of gelator with solvent and inorganic salt can functionalize, activate, or control the properties of supramolecular gels. A lot of work on this area has been done, but all these contributions are only at an early stage. In this work, we tuned the gel formation conditions and properties by using low-molecular-weight gelator (LMWGs), amide-functionalized imidazolium-based surfactant , viz., N-cetyl-N′-acetamido imidazolium bromide ([N-C 16 , N′-CONH 2 -Im]Br), in different solvents and with inorganic salt additives. Under chemical (Cu 2+ /H 2 O 2 ) and physical (temperature) stimuli, gel-sol phase transition occurred in the gel formed from 2 wt% [N-C 16 , N′-CONH 2 -Im]Br in the solvent formamide (FM). Accompanied with increased mechanical strength of the gels, morphology alternation from initial straight stripe-shaped structures to curly belt-like textures was observed in the addition of CuBr 2 . From Small-angle X-ray scattering (SAXS) measurements, bilayer units with interdigitated hydrocarbon tails of the gelator were testified to appear in the gels. Comparative experiments demonstrate that the π-π interaction, H-bonding, and hydrophobic interaction between the gelator molecules are the main driving forces for the gelation . The low-cost gelator, facile preparation, and coordination-driven assembly process make the robust gel a good candidate in various applications, such as material templates and drug deliveries.
This study was aimed to investigate the inhibition effect of thiol-type antioxidants on protein oxidative aggregation caused by free radicals and the underlying mechanisms using six different thiol-type antioxidants ( N -acetyl-L-cysteine, methionine , taurine, alpha-lipoic acid, glutathione and thioproline), Cu 2+ –H 2 O 2 as a free radical generator (mainly a hydroxyl radical generator) and bovine serum albumin as the model protein. The inhibition effect of these antioxidants on protein oxidative aggregation and protective effect against oxidative damage in mouse brain tissues were investigated using SDS-PAGE, intrinsic fluorescence, simultaneous fluorescence, thioflavin T fluorescence, Congo red absorbance and inverted microscope. The results showed that all six antioxidants could inhibit protein oxidative aggregation by scavenging free radicals. In addition, alpha-lipoic acid could also bind to proteins via hydrophobic interactions and thioproline could bind to proteins via hydrogen bonds and van der Waals forces , thereby showing much stronger inhibition effect than others. Moreover, alpha-lipoic acid and thioproline could effectively prevent oxidative damage of mouse brain tissues. These results suggest that alpha-lipoic acid and thioproline can effectively inhibit free radical-induced protein aggregation and brain damage, which are worth testing for further anti-Alzheimer properties.