The Construction Of Functional Supramolecular Biological Nanomaterials Based On Amino Acid Derivatives

It is a challenge for the scientists to construct the biologically similar functional structures of the system by the self-assembly via non-covalent bond between the molecules.It has attracted the attention of the researchers,who make use of biological molecules,such as amino acids,sugars and hormonal molecules to build self-assembly nanomaterial with biological properties.Therefore,taking the advantage of previous research,the amphipathic organic-amino acid compound had been synthesized through amino bond to combine amino acid with fluorescent dyes.In this dissertation,we have designed and constructed the responsiveness nanomaterial based on the amphipathic organic-amino acid.And we have explored the responsiveness of bio-nanomaterial to external stimulus.Last but not least,we have investigated the initial application of bio-nanomaterial.The main contents are as follow:1.Construction of three components p H-responsive biological nanometer functional materials based on isoleucine derivatives.The NVPD has been synthesized via amido bond between the isoleucine and 3,4,9,10-perylenetetracarboxylic dianhydride(PTCDA)molecule.The hydrogel were formed by the three components gelator in the mixed solvent with ultrasound,which the mole ratio of gelator was 1/2/2(NVPD/RF/MM).The π-π aromatic stacking and hydrogen bonding are contribution to construct the formation of the gel.The spectral property of hydrogel was characterized by UV-Vis spectra,fluorescence spectra and FTIR spectra.And the surface topography were observed by laser confocal and scanning electron microscopy.The schematic diagram was proposed.The result showed that the main driving force of the hydrogel were π-π aromatic stacking and hydrogen bonding between the perylene core and amino acid residues.In addition,the biological material has the p H response capabilities and excellent p H-responsive cycles.The biological function of nanomaterial has good application potential in drug delivery.2.Construction of three componentsα-amylase response biological nanometer functional materials based on phenylalanine derivatives.An enzyme-responsive hydrogel had been constructed with α-cyclodextrin(α-CD),vitamin B2(RF)and N,N’-di phenylalanine-3,4,9,10-perylenetetracarboxylic diimide(NPPD),which was synthesized via amido bond between the phenylalanine and 3,4,9,10-perylenetetracarboxylic dianhydride(PTCDA)molecule.The mole ratio of three-component hydrogel was 1:2:1(NPPD: α-CD: RF).The biological gel has a strong fluorescence performance and high mechanical strength.The fluorescence emission spectrum,ultraviolet spectrum,infrared spectrum and laser confocal microscope,scanning electron microscopy(SEM)were used to explore the hydrogel.The result showed that 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.3.Construction of biological nanometer hollow microspheres based on based on phenylalanine derivatives.In this part,we investigated the self-assembly of the N,N’-di tyrosine-3,4,9,10-perylenetetracarboxylic diimide(NTPD)in mixed solvent.NTPD was freely soluble in tetrahydrofuran(THF)and insoluble in water.Due to the stronger cooperation of solvent,it is difference to form the special function materials.The NTPD tend to get together with solvent molecular.When the poor solvent was added in the hybrid liquid,which the volume ratio of the solvent were 8/2,5/5,3/7,respectively,the forming aggregation has changed.The hollow microspheres were be self-assembly in the mixed solvent.With the volume of water increased,the size of opening holes on surface microsphere was smaller,but the diameter of microspheres was bigger.In addition,with the molecular aggregation,molecular fluorescence performance gradually weakened until disappear,possible reason is due to the effect of strong π-π aromatic stacking between the intermolecular causes the fluorescence quenching effect.We explored the influence of different temperature for the hollow microspheres.We set up different freezing temperature and evaporating temperature to investigated how the different temperature regulation of NTPD self-assembly behavior.The self-assembly microstructure of NTPD were observed by SEM.The experimental results show that the self-assembly microstructure of NTPD was different under various freezing time with same evaporating temperature.In addition,we found that the different evaporation temperature plays an important role in the formation of microspheres.The temperature was a vital role for the formation of intermolecular hydrogen bond.In a certain temperature range,the lower the freezing temperature is,the more stable hydrogen bond between NTPD will be.At the appropriate temperature range,THF molecular volatilize,the ball within a certain pressure will be formed in the microsphere internal.Finally the hole of microsphere surface will be formed when the pressure was big enough.