Magnetoinduced Heating Properties Of SAFMO Compounds And Gd-Si-Nd Alloys

In recent years,applying the magnetic heating properties of magnetic nanomaterials to magnetic hyperthermia and magnetic drug targeted therapy has gradually become a popular means of tumor treatment.This technology has become one of the most popular research topics in the field of cancer treatment because of its low damage to the human body,good biocompatibility,targeted treatment,and can be treated alone or combined with traditional therapies.The purpose of materials science researchers is Looking for nano-magnetic materials with suitable magneto-heating properties.However,the current difficulty is that materials with appropriate phase transition temperatures generally do not have high magnetization.In order to obtain materials with suitable omni-directional properties,this article explores the following two contents:1.The SAFMO compound of double perovskite structure with different Al doping amount-Sr_2-xAl_xFeMoO₆(0?x?0.04)was synthesized by sol-gel method,and different chelating agents,different secondary sintering temperature and time,were explored.The influence of different ball milling conditions and the coating of surfactant oleic acid on the structure and performance of the product.The experiment finally concluded that the saturation heating temperature of the Sr_1.98Al_0.02FeMoO₆magnetic fluid coated with oleic acid is 47.8? and the particle size is about 140 nm,which can meet the requirements of mild high temperature(42-48?).In addition,the SAR and ESAR values of Sr_1.98Al_0.02FeMoO₆ coated with oleic acid are 41.8 W·g^-1and 0.0193 W·g^-1·k Hz·(k A·m^-2)respectively,which are higher than many other reports.Experimental results.The level of heat conversion efficiency is positively correlated with the efficiency of magnetic hyperthermia.Therefore,we believe that the Sr_1.98Al_0.02FeMoO₆ magnetic fluid coated with oleic acid is a good candidate for hyperthermia.2.Gd-Si-Nd alloys with different Nd doping amounts were prepared by the smelting method,and the highest purity alloy phase can be obtained by selecting annealing conditions of 800? and annealing for three days.By doping with Nd,the saturation heating temperature can be reduced to a large extent,and the phenomenon of excessive heating can be effectively prevented.The combination of high-energy ball milling and planetary ball milling can obtain sheet-like nanoparticles with a high degree of homogeneity.The sheet-like particles have the highest specific surface area under the same volume,and can achieve greater drug loading in magnetic drug targeted therapy.The stimulation of the external alternating magnetic field can induce the magnetic nanoparticles to generate heat and trigger the release of the drug.The drug release efficiency is positively correlated with the heat generation efficiency(SAR)of the magnetic nanoparticles.In the experiment,the thermal conversion efficiency measured and calculated with a solid sample is lower than the thermal conversion efficiency measured in a liquid solvent.The main reason is that the heating mechanism of the solid sample is mainly Hysteresis loss,and the measurement in the solvent not only contains Hysteresis Loss also includes Brownian Relaxation.