Adaptive Modification Of Magneto Optical Multifunctional Mn < Sub > 3 < / Sub > O < Sub > 4 < / Sub > @ The Sio < Sub > 2 < / Sub > Nanoparticle Preparation Of Contrast Agents And Biological Applications

Magnetic resonance imaging, referred to as nuclear magnetic resonance,magnetic resonance is a new imaging technique developed in the1980s. Its full nameis: nuclear magnetic resonance computer tomography。It is a new medical imagingtechnology for medical diagnosis. In order to improve the resolution of soft tissue, weused the contrast agent so that part of the incurable diseases to be diagnosed. Theclinical application of contrast agent must meet the following requirements: lowtoxicity, high relaxation efficiency, better water-soluble, with targeted and easilyexcreted in the body stable.Fluorescent molecular markers of Mn₃O₄nanoparticles have the potential ofmulti-function testing, and magnet-optical dual-function imaging and target effects atthe cellular level. Mn₃O₄nanoparticles as a T1contrast agent has an advantage inmany ways:（1） high relaxation performance, with positive reinforcement contrasteffects;（2） nanostructures can be extended in vivo circulation time;（3） water-solubleshould be good, through the blood-brain barrier imaging of the brain. Mn₃O₄nanoparticles contrast agent is not of great significance to the future applicationof the T1nanoparticles contrast agents. Therefore, we synthesized the aptamermodified with multi-function of Mn₃O₄@SiO₂nanoparticles magnet-optical contrastagent through experimental characterization. It showed that the synthesized contrastagent has certain clinical reference value.First, Mn3O4nanoparticles were prepared by hydrolysis, Then TEOS is coatedon the surface of Mn₃O₄particles through hydrolysis, and then to solve the watersolubility and stability of the Mn₃O₄nanoparticles, to connect the fluorescent materialoutside of the nanoparticles, The APS is joined on the surface of Mn₃O₄@SiO₂nanoparticles, thereby the nanoparticles surface access large amine, andfinally connect the fluorescent substance: Rhodamine and targeted substances:Aptamers. So Mn₃O₄@SiO₂-NH2（RITC）-Apt nanoparticles are synthesized. Itshowed that the contrast agent with low cytotoxicity in cell, Importantly,Mn₃O₄@SiO₂-NH2（RITC）-Apt nanoparticles have very good enhanced MR imagingresults about HeLa cells. Mn₃O₄@SiO₂-NH2（RITC）-Apt nanoparticles are expected to be used for cancer diagnosis and therapy.