Popis: |
Surface modified cobalt ferrite (CoFe 2 O 4 ) nanoparticles containing Ni–NTA affinity group were synthesized and used for the separation of histidine tag proteins from the complex matrices through the use of imidazole side chains of histidine molecules. Firstly, CoFe 2 O 4 nanoparticles with a narrow size distribution were prepared in an aqueous solution using the controlled co-precipitation method. In order to obtain small CoFe 2 O 4 agglomerates, oleic acid and sodium chloride were used as dispersants. The CoFe 2 O 4 particles were coated with silica and subsequently the surface of these silica coated particles (SiO 2 –CoFe 2 O 4 ) was modified by amine (NH 2 ) groups in order to add further functional groups on the silica shell. Then, carboxyl (–COOH) functional groups were added to the SiO 2 –CoFe 2 O 4 magnetic nanoparticles through the NH 2 groups. After that Nα,Nα–Bis(carboxymethyl)- l -lysine hydrate (NTA) was attached to carboxyl ends of the structure. Finally, the surface modified nanoparticles were labeled with nickel (Ni) (II) ions. Furthermore, the modified SiO 2 –CoFe 2 O 4 magnetic nanoparticles were utilized as a new system that allows purification of the N-terminal His-tagged recombinant small heat shock protein, Tpv -sHSP 14.3. |