The Determination Of The Optimum Technological Conditions Of Superparamagnetic Iron Oxide And The Preparation And Molecular Structure Validation Of SPIO-PLL Nanoparticles

Objective：To determine optimum technological conditions for thereparation of the superparamagnetic iron oxide (SPIO) nanoparticlesodified by dextran polylysine, and to evaluate the quality of the product.Methods：An extensive study was made on the optimum technologicalonditions of SPIO from four factors affecting its hydrodynamic size inrthogonal experiments. SPIO nanoparticles was synthesised underptimum technological conditions；the shape of products and hydrodynamicize were detected by TEM and Malvern Zetasizer espectively，the contentf Fe of products were detected by atomic absorption spectrophotometer，hile chemical structures of SPIO was characterized and analyzed usingTIR method, X-ray powder diffraction method to identify thengredients，and the magnetic parameters measurement by vibrating sampleagnetometer. Furthermore, ovarian cancer cells experiments was utilized to primarily validate magnetic property of SPIO.Results：The results of the orthogonal experiments showed that theoptimum technological conditions: the concentration of dextran is10mg.mL-1,the optimum pH is about10, the reaction temperature is80℃andthe stirring rate is600r.min-1. The TEM results showed the SPIO particleswere spherical shape、homogeneous distribution and uniform in size, and theparticle size was less than10nm. The distribution size of SPIO particles was7.0nm, dispersion was0.059. The content of Fe of products was12.360±0.08mg.ml-1. The IR results clearly proved that the Fe3O4wascoated by dextran successfully. X-ray powder diffraction method fordetermination of sample composition Fe3O4, Magnetism parameters prompthave superparamagnetism. The ovarian cancer cells experimentsdemonstrated that SPIO had entered into the cell and then the cells withmagnetism had certain magnetic properties.Conclusion: SPIO nanoparticles whose synthesis under optimumtechnological conditions through the orthogonal experiments were stable、small particle size、good dispersion and able to enter ovarian cancer cells andthen the cells with magnetism had certain magnetic properties. And it willlay a certain foundation for specific tumor probe preparation. Preparation,molecular structure validation and space formharacterization of SPIO-PLL nanoparticlesObjective：To explore the preparation, structure validation and spaceform characterization of SPIO-PLL nanoparticles, which was coated byDextran then modified by polylysine.Methods：A novel type of nanoparticles was prepared on the basis ofsuperparamagnetic iron oxide (SPIO) obtained by coprecipitation, and thensuperficial modified with polylysine. The hydrodynamic size、zeta potentialand shape of products were detected by Malvern Zetasizer and TEM.Meanwhile the connection of products was characterized by GPC, IR and1HNMR. Furthermore, High-resolution atomic force microscopy (AFM)was utilized to characterize the molecular structure of products and theinteraction between SPIO coated by Dextran and PLL.Results：The hydrodynamic size、zeta potential and TEM results showthe average size and zeta potential of products was7.37nm,13.6mV,respectively. The successful connection of SPIO and PLL was proved byGPC, IR and1HNMR. Moreover, AFM·IPC-208B findings clearly revealedthe successful connection of SPIO and PLL was in form of imine linkage.Conclusion：A novel type of good quality SPIO-PLL nanoparticleswhose average size was7.37nm was prepared and it will lay a certain foundation for specific tumor probe preparation.