Growth Of Metal-Organic Frameworks On TiO₂ Nanotubes And Study Of Their Application In Purification Of Green Fluorescent Protein

Metal-organic frameworks(MOFs),as a new type of material,have attracted immense attention by reason of their high surface area,good thermal stability,uniform structured nanoscale cavities,excellent mechanical stability,and tunable surface properties.Therefore,these properties endow MOFs with great potential for a variety of applications,for instance,gas storage and separation,heterogeneous catalysis,chemical sensors and drug delivery.Therefore,we study the application of metal-organic frameworks in the protein separation in this paper.The first chapter gives a brief describe for the concept,properties and applications of metal-organic frameworks,while the preparation and application of titania nanotubes as well as titania nanotubes are described in detail.The applications of nanomaterials in protein separation are also discussed in the text.In the end,we give a brief summary for the significance of this topic.The second chapter mainly studies the preparation of Ni-MOF@TiO2 NTs and the exploration of its application in separation and purification of His-tagged green fluorescent protein(His-tagged GFP).In this chapter,we prepared NiO/TiO2 NTs by anodic oxidization.Ti-MOF or Ni-MOF modified TiO2 NTs were prepared by using p-benzenedicarboxylic acid(PTA),1,3,5-benzenetricarboxylic acid(H3BTC)and 4,4'-bipyridine(bipy)respectively as organic ligands.The distribution of MOFs prepared on different ligands on nanotubes and their stability in aqueous solution were investigated.The method of selective growth of Ni-MOF was explored and the MOFs modified TiO2 NTs were characterized by SEM,TEM,XRD,Zeta potentiometer,BET,TGA and other methods.The MOFs modified TiO2 NTs were used for the separation and purification of His-tagged GFP.The adsorption properties of TiO2 NTs on His-tagged GPF before and after MOFs modification were investigated.The Ni-MOF@TiO2 NTs with excellent adsorption capacity of His-tagged GPF in a wide range were systematically studied.The optimal adsorption conditions and elution conditions were explored and the adsorption mechanism was discussed.It is proved that the Ni-MOF@TiO2 NTs can be reused as a filter for many times and can enrich 262 times of low-concentration His-tagged GPF.His-tagged GPF separated by the membrane has high purity and adsorption.The elution process does not affect the conformation and activity of the His-tagged GFP.