Preparation, Characterization And Application Of Fe₃O₄Magenetic Nanoparticles

As a special nanomaterial, magnetic nanoparticle has many good qualities, not only as a nanoparticle, but also as a magenetic material, for example, surface effect, finite-size effect and magenetic. Owing to the good properties, magenetic nanoparticle has many potential appications in many fields, especially in biology. Surface modified magnetic nanoparticle has more applications, because it has less aggregation and better biological compatibility. Because of the good biological compatibility, good degradation and abundant hydroxyl, dextran is the best choice for the modification material.In this essay, we used two methods to prepare magnetic nanoparticle. one is chemical co-deposition method, in which was precipated from the raw material Fe2+,Fe3+in ammonia water. Another is high temperature decomposition method, in which Fe(acac)3was decomposed at a high temperature in2-pyrrolidone.In this essay, we discussed the use of the magnetic nanoparticle. First, we synthesized magnetic nanoparticle using chemical co-deposition method and modified it with carboxymethyl dextran (CMD), then using anti-E.coli O157:H7to react with CMD to synthesize a new immunomagnetic nanoparticle to detect and separate the E.coli O157:H7.