SYNTHESIS AND PROPERTIES OF BIOGENIC MAGNETITE SYNTHETIC ANALOGUES

This paper deals with different factors (ultrasonication, magnetic field) in determining the properties of synthesized magnetite nanoparticles. Development of technologies for creating synthetic analogues of magnetic minerals localized in human and other living organism tissues is of great importance in solving a wide range of mineralogical, medical-biological and material science problems. Magnetite is one of the physiological biominerals in living organisms, its formation being genetically determined. Magnetically ordered biogenic nanoparticles of iron oxides and hydroxides, which are biominerals, are known to realize a wide range of biological functions, including animals' orientation in space, and to play an important role in brain functioning. Migratory birds, bees, fish develop a sense of direction in space ("magnetic compass") due to the presence ofmagnetite, which is why this vital biomineral is of wide scientific interest. The paper describes the methods of magnetite nanoparticle synthesis using a magnetic field and ultrasound. Co-precipitation is described asone of the easiest chemical methods of synthesizing magnetic nanoparticles. Samples were synthesized by employing the method of co-precipitation of Fe3+ and Fe2+ salts in an alkaline medium involving ultrasound and magnetic fields. X-ray diffraction and magnetometry were usedto study the samples. Special attention was given to the magnetic properties and determining the crystallite size of the produced mineral. The research results showed a correlation between the crystallite size and various synthesis conditions. With ultrasound applied, the size of thesynthesized nanoparticles tends to be bigger as compared to that of the nanoparticles obtained without ultrasonication. It was determined thatmagnetization of samples increases with the increase in the size of nanoparticles. The research results are summarized in the tables and illustrations presented in the paper. The obtained data can be used for developing and improving the technologies for biogenic magnetite analogua synthesis. The paper could be of use to teachers, students, and researchers interested in biomineralogy and magnetic nanoparticle synthesis.