Study On Preparation And Properties Of Mg-Zn Ferrite Composites For Tumor Hyperthermia

Magnesium-zinc ferrite nanoparticles are considered as a kind of low toxicity material and have many excellent properties which have been widely used in many fields.However,the study of Mg-Zn ferrite is not comprehensive enough in the temperature control of tumour hyperthermia,and the heating time and thermal stability of the material need to be improved.Carbon nanotubes have broad application prospects in the field of composite materials due to their particular structure and unique physical properties.There are many studies on the thermal properties of carbon nanotubes and their composites.The thermal properties of carbon nanotubes and their composites can be well changed by using carbon nanotubes to prepare composites.Adding carbon nanotubes to Mg-Zn ferrite may improve the heating rate and stability of the material,and may also improve the thermal efficiency of the material.Besides,various tudies have shown that folic acid has special functions in the diagnosis and treatment of tumors.Therefore,in this study,a novel carbon nanotube-doped Mg-Zn ferrite composite was designed and fabricated based on the unique properties of Mg-Zn ferrite and carbon nanotubes.According to the high expression of the folate receptor in cancer cells,the surface modification experiment of ferrite was designed.XRD,SEM,TEM,VSM,FT-IR,Zetasizer Nano ZSE nanoparticle size analyzer,induction heating equipment and other testing instruments were used to test and analyze the materials.The specific contents and conclusions are as follows:(1)Spinel Mg-Zn ferrites with good crystallinity and high purity were prepared by the coprecipitation method.The morphology,particle size,magnetic properties and heating rate of the materials can be effectively controlled by the change of zinc doping amount and calcination temperature.The ANOVA analysis showed that the amount of dopied zinc and calcination temperature would affect the magnetic properties and heating properties of the samples.The increase of Zn2+ can change the superexchange effect of A and B positions in ferrite,which increases magnetic properties first and then the decrease of magnetic properties.The thermal effect test of Mg-Zn ferrite shows that the heating trend of the material is affected by hysteresis loss.Certain technological conditions can change the magnetic properties of the material and affect the heating trend of the material.The increase of calcination temperature promotes the temperature rise of the sample,while the increase of zinc content inhibits the temperature rise of the sample.The thermal effect curve of Mg0.4Zn0.6Fe2O4 nanoparticles prepared at 500? in the alternating magnetic field shows that the sample can rise to 43? in 3 minutes and remain for 57 minutes in the range of 43?50?,indicating that the material can be used as a potential heat source material for magnetic hyperthermia of tumours.(2)Carbon nanotubes doped Mg-Zn ferrite composites were prepared by the coprecipitation method.Carbon nanotubes doping can improve the aggregation of ferrite particles.The doping amount and calcination temperature of carbon nanotubes affect the magnetocaloric properties of the materials.When the calcination temperature is low or too high,the doping amount of carbon nanotubes has a significant influence on the magnetocaloric properties of the materials.A small number of carbon pipes can accelerate the heat transfer between grains,and the grains with poor magnetocaloric properties can increase the temperature under the drive of grains with excellent magnetocaloric features.However,when there are too many carbon nanotubes,the heat dissipation between grains is too fast,and the temperature rise is slowed down.When the calcination temperature is between 500?600?,the calcination temperature plays a do minant role in affecting the magnetocaloric properties of the material,and the material has the best magnetocaloric features.(3)Carboxyl group and folic acid were used to modify the surface of ferrite.The modified ferrite was still pure spinel Mg-Zn ferrite.The surface modification did not affect the composition and phase of the material,but had an effect on the magnetic properties of the original ferrite.At the same time,surface carboxylation can increase the repulsion between particles and improve the dispersion of materials.In the infrared spectra of carboxyl-modified Mg-Zn ferrite,the stretching vibration peak of C=O in carboxyl group appeared at 1735 cm-1,which proved that the carboxyl group was successfully modified on the surface of ferrite.In the study of different modification methods,the amount of folic acid and the type of activator affect the effect of the folic acid modification.When DCC and HOSu are used to activate carboxyl groups,it is difficult for a mino groups on folic acid to react with activated carboxyl groups when folic acid is too low.With the increase of folic acid,the characteristic peaks of folic acid in infrared spectra become more and more obvious.When EDCI and HOSu were selected to activate the carboxyl group,the reaction efficiency of amide reaction was low,and the effect of folic acid modification was poor.