Preparation And Drug Loading Properties Of Core-shell Mesoporous Silica Fe₃O₄ Nanocomposites

Objectives:1.In order to improve the monodispersity and drug-loading properties of magnetic nanometer particles of Fe₃O₄?MNPs?,the amphoteric surfactant betaine or sulfobetaine were used to modify MNPs.Modified materials were further encapsulated by mesoporous silicon to form mesoporous silicon magnetic composites with a core-shell structure with the purpose of wider function and application.2.The drug-loading properties of composite materials{taking doxorubicin hydrochloride?logogram as DOX?as an example}and the activity of HeLa cells in vitro after drug loading were studied.Methods:1.In order to decrease the agglomeration of Fe₃O₄ particles and increase the specific surface area of the material,the amphoteric surfactant betaine or sulfobetaine were used to modify MNPs,which can effectively improve the monodispersity of the material,and obtain BMNPs or SBMNPs.Modified materials were encapsulated by the SiO₂ generating from tetraethyl silicate encapsulates to obtain?S?BMNPs@SiO₂.Further,SiO₂ containing cetyltrimethylammoniumbromide?CTAB?astemplateisaddedtoobtain?S?BMNPs@SiO₂@CTAB/SiO₂,which was etched using sodium carbonate and calcined to synthesize mesoporous silicon magnetic nanocomposites MNPs@HMSS-O?hollow mesoporous silica spheres with oriented mesoporous shell,HMSS-O?with a core-shell structure.The synthesized materials were further characterized and analyzed.2.Two synthetic nanocomposites were combined with DOX using ultrasonic and shaker.The encapsulation efficiency and the drug loading rate of the magnetic nanocomposite with DOX were determined by the UV-vis spectrophotometer?UV-vis?and the release capacity of inclusion object were also evaluated in vitro.3.The effects of two DOX-loaded magnetic nanocomposites on the growth of HeLa cells were investigated by MTT colorimetry.Results:1.Two types of betaine were successfully modified MNPs,which can effectively improve the monodispersity.Modified materials were further coated SiO₂,etched,and calcined to form mesoporous silicon magnetic nanocomposites with a core-shell structure with the purpose of increasing the drug loading rate.2.Two types of composite materials MNPs@HMSS-O have good inclusion properties in vitro and drug release for DOX.3.Two types of composite materials MNPs@HMSS-O have obvious inhibiting effect on the growth of HeLa cells.Conclusions:1.The two types of magnetic nanocomposites have small particle size,large specific surface area and suitable magnetic induction intensity.2.The two types of magnetic nanocomposites have excellent package interactions for DOX,and the release rate and time are in line with the requirements.3.The inclusion of DOX in two types of magnetic nanocomposites can effectively inhibit the proliferation of HeLa cells,indicating that the synthesized composite material has good biocompatibility and does not change the efficacy of DOX.