SYNTHESIS AND RHEOLOGICAL PROPERTIES OF AN AQUEOUS

Ferrofluids are very stable colloidal dispersions of ultra-fine particles of a magnetic material, such as magnetite, in a liquid, which may be chosen to conform to a particular application. Since in future the applications of the ferrofluids will focus more toward the biological uses where the ultra-fine ferrophase is particularly important for the penetration of the cell structures. In these applications, it is proper to have a biocompatible solvent such as water at optimum pH, also. Ferrofluids containing superparamagnetic Fe3O4 nanoparticles have been prepared by a chemical precipitation method. The aggregation of the particles was prevented by using citric acid. Physical tests have been performed on two samples of the ferrofluid prepared by us (consisting mainly of Fe3O4 ultra-fine particles stabilized with citric acid and immersed in water). Physical tests have been performed on these samples