Study On Multi-functional Magnetic Nanoparticles Vector

The purpose of this study is to prepare O-carboxymethylated chitosan(O-CMC) and chitosan–lysine(CS-Lys) coated magnetic nanoparticles using co-precipitation method. The condition of synthesis of magnetic nanoparticles is also discussed. In this study, we found the optimum conditions for synthesizing magnetic nanoparticles. The results showed that the average sizes of magnetic nanoparticles were about 100nm and still retained well-shaped morphology with narrow size distribution.The average sizes of O-CMC magnetic nanoparticles and CS-Lys magnetic nanoparticles are about 100nm and still retained well-shaped morphology with narrow size distribution and magnetic properties that are close to suerparamagnetic matters by TEM, IR, Particle Size Analyzer, Zeta Potential Analyzer, Vibrating Samples Magnetometer, XPS and X-ray diffraction measured and characterized.The magnetic carries nanoparticles absorbed pGFP on the surface. The ratio of O-CMC magnetic nanoparticles uploaded is 64.7%. The CS-Lys magnetic nanoparticles is 80.1%. In vitro study we have demonstrated that the magnetic carries nanoparticles can deliver reporter gene pGFP expressing green fluorescent protein. By the Luciferase Assay System we tested the transfection efficiency. The cytotoxicity grade was tested by MTT. The result showed that the O-CMC magnetic nanoparticles and CS-Lys magnetic nanoparticles were both cytotoxicity grade 1 by national standard.We coupled Tat and Transferrin on the surface of O-CMC magnetic nanoparticles to form Tat mediated magnetic nanoparticles having composite targeting function. The biodistribution of Tat-Tf-O-CMC magnetic nanoparticles was further investigated by 99Tc-labeled SPECT. Tat-Tf-O-CMC magnetic nanoparticles successfully passed the blood-brain barrier under the magnetic field.