Multifunctional Fe3O4@SiO2-CDs magnetic fluorescent nanoparticles as effective carrier of gambogic acid for inhibiting VX2 tumor cells

This paper reports a dual-functional platform that can be used for synergistic therapy, including drug release and magnetic targeting. The platform is realized through an amide reaction between high-fluorescence carbon quantum dots (CD) prepared by microwave method and amino-functional Fe3O4@SiO2 with high saturation magnetic strength and a core-shell structure to obtain multifunctional magnetic fluorescent nanocomposite particles Fe3O4@SiO2-CDs. The structure, drug release behavior, cytotoxicity, fluorescence and distribution in vivo of Fe3O4@SiO2-CDs nanoparticles were studied. The results show that the Fe3O4@SiO2-CDs with a dynamic diameter of about 155.0 nm and a magnetic saturation intensity of 31.2 emu/g has a higher loading of gambogic acid (GA), and is more conducive to drug release in an environment of pH = 5.7. In addition, Fe3O4@SiO2-CDs has low cytotoxicity and can enter VX2 cells. However, GA-loaded Fe3O4@SiO2-CDs has an inhibitory effect on VX2 cells, and the cell survival rate is less than 20% at a concentration of 100 μg/mL. Magnetic targeting experiments show that bifunctional magnetic nanoparticles have an outstanding magnetic targeting effect on tumors. [Display omitted] •Highly magnetized and core-shell structured Fe3O4@SiO2-CDs was synthesized.•Fe3O4@SiO2-CDs has a pH dependency on the releasing of GA.•Fe3O4@SiO2-CDs (GA) loaded with GA had an inhibitory effect on VX2 cells.•Dual-functional nanoparticles have strong magnetic targeting capacity on tumors.