The Synthesis Of Fe-Co Cu-Ni Nano-materials Using Apoferritin As A Biomimetic Templated

In this article, we mainly research the process of synthesizing protein coated Fe and Co nano particle, using the apoferritin as a biological template, the Co(NO3)2-6H2O and Fe(NH4)2(SO4)2-6H2O as a raw and processed material, simultaneously, using the NaBH4as a reducing agent. Furthermore, we use a variety of different analysis methods to analyze or characterize the obtained samples, to determine the suitable reaction conditions, such as the concentration of the reaction solution, the temperature of the reaction solution and the PH of the buffer solution. In the same time, we also analyzed and characterized the appearance pattern and size of the nano-particle, the relative content of the elemental composition, the physical or chemical properties and the crystal structure of the prepared nano-particle. Finally, using this method, we success to synthesis the Fe and Co nano magnetic particles which were coated by apoferritin, possessed obvious single crystal lattice structure, with an about5-7nm particle diameter. At the same time, we also studied the synthesis of the Cu-Ni nano-particles, using the acetic acid copper and nickel nitrate as raw materials by the biological template method. And through analysis and characterization the sample, proved that the Cu-Ni nano-particles having a particle diameter of about6nm, and showed the feasibility of the synthesis of the bibasic metal nano materials by the biological template method, provided the reference for the synthesis of the bibasic metal nano materials.Using the transmission electron microscope as analysis method, we analyzed and characterized the prepared Fe and Co nano-particles, found that there are many black nano-particles in the sample whose particle diameter is around5-7nm, and evenly distributed, with a high degree of dispersion, no obvious aggregate. Meanwhile, we analyzed and characterized the pure apoferritin which was stained by the uranium acetate, found that there are many white spots with a diameter of about8-9nm in the TEM picture of the pure apoferritin. That is due to the protein molecules become darker in color after stained, while the protein cavity have no change. We found that there is a distinct black particle in the protein cavity through observing the TEM picture of the Fe-Co sample which was stained by the uranium acetate; this is the Fe-Co nano particle we synthesized. That is to say the nano particles are synthesized in the protein cavity. Otherwise, we analyzed the EDS spectrum of the sample in micron region, found that there are clearly Fe and Co energy spectrum peak in the EDS spectrum. This indicated that the black nano-particles in the TEM photo is Fe or Co metal, or may be a mixture of both. But also from the height of the energy spectrum peak, we can find that the two peak’s height is almost uniform, indicating that the relative content of the Fe and Co is same in the black nano-particles, can be considered that the Fe and Co assemble in the accordance with3:1ratio. Based on the selected area electron diffraction characterization of the Fe-Co sample for many times, we have failed to find significant electron diffraction patterns. Through inquiring relevant information, preliminary estimates that the Fe-Co nano-particle existed in a form of indefinite. So we should do a further research and analysis in the existing form and lattice structure of the Fe-Co sample in future.We have done the same analytical and characterization for Cu-Ni sample, and found that the particle diameter of the Cu-Ni sample is about6nm. In the EDS analysis, because of the use of Cu network, the absorption peak of Cu element in the sample was covered, so we can only found the absorption peak of Ni element. In order to determine the relative content of the Cu and Ni in the sample, we plan to do a further analysis of the sample using C network. By observing the selected area electron diffraction pattern of the Cu-Ni sample, we found that there are clearly and distribution rule speckles in the electron diffraction pattern. This is same to the electron diffraction pattern of the crystal structure material’s characteristics. That is to say the apoferritin coated Fe-Co nano-particles which were synthesized by the biological template have the crystal lattice structure, and the Fe and Co nano-particles belong to the category of the crystal.UV-Vis spectral analysis was used to analyze and characterize the solution of the sample. From the spectral line, we can find an obvious absorption peak in the610nm before the reduction reaction, which is the typical characteristic absorption peak of the Fe+and Co2+. But after the reduction reaction, the absorption peak significant weakening or even disappear, which indicated that the Fe2+and Co2+were reduced by the reducing agent NaBH4, and the Fe+and Co2+changed into the Fe and Co metal atom; In addition, there is an obvious absorption peak in the280nm, which is the typical characteristic absorption peak of apoferritin, and the position and height of the absorption peak have no change before and after the reduction reaction. That is to say the apoferritin is only a biological template which is used to constrain the nano-particles growth in the process of the sample preparation.In a short, the bibasic metal Fe-Co Cu-Ni nano material which were synthesized by the biological template method not only have the merit of a small particle diameter and particle size distribution, but also have good biological compatibility because the nanoparticles were coated in the apoferritin cavity. So these nano materials have a very good application prospect as targeting drug carrier in biomedicine.