Self-assembly Of Peptides/Proteins Into Chiral Nanostructures And Its Application In Separation And Catalysis

Biological macromolecules such as polysaccharides and proteins are widely used in the separation and catalysis of various components due to their inherent chirality.Peptide can self-assemble into various chiral supramolecular nanostructures by non-bond interactions.At present,the research on the application of the supramolecular nanostructure in chiral separation and biomimetic catalysis is becoming a hot topic in scientific research.In this paper,the effects of peptide sequence,pH,solvent,and interface on the formation of supramolecular nanostructures were studied by functionally modified polypeptide molecules and amyloid protein.Furthermore,the peptide supramolecular nanostructure and the amyloid protein nanofiber were applied to the chiral separation and biomimetic catalysis.(1)In this paper,the self-assembly behavior of Fmoc-FFK in water/organic mixture solvent was investigated.Based on Fmoc-FFK tripeptide,two other Fmoc tetrapeptides,Fmoc-FFKK and Fmoc-FFKD,were designed.At different pH,Fmoc-peptides form supramolecular nanostructures with different morphologies,such as nanoflowers,nanospheres,nanofibers,nanosheets and so on.Furthermore,the peptide supramolecular nanostructures formed at different pH were applied to the resolution of racemic mixtures of 2-phenylpropionic acid(PPA)and 1-phenylethanol(PT).The results showed that the peptide supramolecular nanostructures had high enantiomeric separation efficiency,up to99.99%.The enantioselectivity results of various enantiomers show that electrostatic interaction,hydrophobic and hydrogen bonding interaction have an important influence on the chiral resolution of various supramolecular nanostructures.(2)The amyloid fibrils were synthesized from β-Lactoglobulin(β-LG),BSA and lysozyme under acid heat condition.The chiral resolution of three kinds of protein molecules and amyloid fibrils was studied.It is proved that protein molecular fibrosis can reduces the enantiomeric separation efficiency of proteins to chiral drugs.(3)The self-assembly of ferrocene phenylalanine dipeptide(FC FF)into amyloid nanofibers was controlled by high-temperature water vapor annealing.These nanofibers can grow directionally on the solid surface and twist together to form a long-range ordered hierarchical helical array(HHAs).Due to the existence of ferrocene group,HHAs has redox activity,and can realize the in-situ growth of gold nanoparticles(Au NPs)on its surface,forming HHAs & Au NPs composite structure,which has excellent catalytic activity.