The Construction Of Responsive Biological Nanomaterials Based On Amino Acids

How to control the intermolecular interactions to realize the self-assembly of biological molecules into functional nanostructures is a long-term challenge.Therefore,taking the advantage of forming ordered nanostructure and the biocompatibility to prepare biological self-assembled nanostructures is the hot topic.In this dissertation,firstly,we have constructed the nanomaterials of responsiveness based on the former research.Then we have explored the responsiveness of bio-nanomaterials to external stimulus.Last but not least,we have investigated the initial application of bio-nanomaterials.The main contents are as follow:1.Construction of bi-components biological nanomaterials based on isoleucine.The distinctive structure of biological nanomaterials was obtained through the self-assembly of N,N′-diisoleucine-1,4,5,8-naphthalene tetracarboxylic acid diethylamide（IN）and bases（A,T,G,U）.The nanostructures exhibited that the IN/A=1/1.5 tend to self-assemble into nanotube,while IN/T=1/1.5 trend to self-assemble into nanofibers.However,the morphology of IN/G=1.5/1were hollow nanosphere structures,and the self-assembled structure of IN/U=2/1 were nano-silk.Through the UV-Vis spectra,fluorescence spectra and FTIR spectra,the schematic diagram was proposed.The driving forces of the biological nanomaterials were the hydrogen bonding interactions between amino acid residues and bases,the π-π interactions and also the cooperation of solvent.2.Construction of bi-components stimuli-responsive biological nanomaterials based on phenylalance.4,4-bipyridyl（BP）and phenylalanine-functionalized perylene derivatives（PP）,valine-functionalized perylene derivatives（VP）,aspartic-functionalized perylene derivatives（AP）,were self-assembled into stimuli-responsive luminescent organic gels,respectively.The organogels displayed strong fluorescence,superior mechanical properties and responsive to acid and alkali.The results of UV-Vis spectra,fluorescence spectra,FTIR spectra and scanning tunneling microscopy demonstrated the formation mechanism of the hierarchical self-assembly of the organogel.3.The responsiveness of the biological nanomaterials to the external stimuli.1)The influence of polarity of solvents to the biological nanomaterials.The self-assembly behaviors of phenylalanine-functionalized perylene derivatives（PP）were investigated in solvents with different polarity.PP was soluble in THF,which led it hard to observe regular morphology,while the solvent turned to VTHF/VH2 O = 8/2,nanosphere structures were formed.When the solvent was VTHF/VH2 O = 5/5,nanosphere structures tended to get together.Interestingly,the nanosphere structures were replaced by nanofibers when the solvent was VTHF/VH2O=3/7.As the solvent was transform into H2 O,the nanofibers assembled into slice structure.In addition,as the content of H₂O increasing,the fluorescence intensity decreased and the reversion of chirality of these structures turned out.2)photo-responsive of the biological nanomaterials.Tyrosine functionalized perylene derivatives（PP）and folic acid（FA）self-assembled into biological nanostructures.Then the spectra methods were utilized to detect the difference of the assembly behaviors of PP/FA after 30 min of irradiation.The result of CD exhibited that there was no obvious signal before irradiation,while there was negative cotton effect at 308 nm,436 nm and 648 nm,and a positive cotton effect 398 nm,which could be attributed to the split of FA.4.The initial application of biological nanomaterials.Hydrogels were obtained via the self-assembly behavior of Glutamate-functionalized perylene derivatives（GP）,melamine（MM）and riboflavin（RF）.The hydrogel was nanofiber structures with excellent fluorescence and superior mechanical properties.The cell viability test of the hydrogels indicated the perfect biocompatibility.Then the cumulative release of RF from the hydrogel illustrated the high sustained release effect and time-dependent the growth of E.coli at different concentration declared the hydrogels accelerated the growth of E.coli with the proper concentration of 5μg/mL.