Preparation Of New Type Bis (5-methyltetrazolium) Amine Absorbent And Its Absorption Perfor Mance Research

Nowadays, immobilized metal affinity chromatography （IMAC） has been widely used in the field of biomacromolecules separation and purification, as well as the field of absorption for heavy metal ions. Ligand structure has an important effect on the absorption for heavy metal ions and protein separation selectively. This thesis designs a new-type 5-methyltetrazolium amine tridentate ligand on the preliminary works, which was fastened on the Fe₃O₄ magnetic nanoparticles and resin, respectively. And the protein adsorption property of the chelated Cu（II） magnetic nanoparticles and the absorption property for ion metal ions of resin were investigated. The full text work includes two parts:1. Fe₃O₄@SiO₂ particles with core-cell structure were prepared by hydrothermal method and Stober method. And Fe₃O₄@SiO₂ particles reacted with [4-（chloromethyl）phenyl]trimethoxysilane, tris（2-aminoethyl）amine, bromoacetonitrile and sodium azide in sequence to prepare bis（5-methyltetrazolium）amine-bonded magnetic nanoparticles. The physical properties of absorbent, including X-ray photoelectron spectroscopy （XPS） and Zeta potential, were characterized. The adsorption of proteins on the chelated Cu（Ⅱ） adsorbent, as well as the influences of the pH value of solution, salting strength and initial protein concentration, were evaluated with lysozyme, cytochrome C and chymotrypsin. The results illustrated that the absorption of protein was proceed via metal coordination mechanism and was also in accordance with Langmuir absorption model. In addition, the chelated Cu（Ⅱ） absorbent was employed to absorb protein mixture, showing that this new type of absorption had selective absorption to protein mixture. These results illustrated that the metal-chelated absorbent had potential application value in selectively separating and enriching proteins.2. Chloromethylpolystyrene resin reacted with [4-（chloromethyl）phenyl] trimethoxysilane, tris（2-aminoethyl）amine, bromoacetonitrile and sodium azide in sequence to prepare bis（5-methyltetrazolium）amine-bonded resin. The absorbent was characterized by FT-IR, X-ray photoelectron spectroscopy （XPS）, specific surface area and pore size analyzer. The adsorption capacity of the resin on Cu（Ⅱ）, Ni（Ⅱ） and Cd（Ⅱ）, as well as the influences of the solution pH value and salting strength on the adsorption capacity, absorption isotherm, absorption kineties, absorption amount and removal rate were investigated, regenerability. The results showed that adsorption capacity of the resin on Cu（Ⅱ）, Ni（Ⅱ） and Cd（Ⅱ）,could reach the best, when the solution pH value reach 5,6 and 6, respectively. The reaction between metal ions （Cu（Ⅱ） and Ni（Ⅱ）） and resin was based on the chelation to absorb metal ions. The absorption on resin surface was accord with Langmuir absorption model and secondary dynamic model. With the absorbent amount increasing, the removal rates of Cu（Ⅱ）, Ni（Ⅱ） and Cd（Ⅱ）, continuously increased. And the absorption capacity on Cu（Ⅱ）and Cd（Ⅱ）, increased first and then decreased, while the absorption capacity on Ni（Ⅱ） decreased continuously.