Load and release of gambogic acid via dual-target ellipsoidal-Fe₃O₄@SiO₂@mSiO₂-C₁₈@dopamine hydrochloride -graphene quantum dots-folic acid and its inhibition to VX2 tumor cells

Abstract Ellipsoidal-Fe 3 O 4 @SiO 2 @mSiO 2 -C 18 @dopamine hydrochloride-graphene quantum dots-folic acid (ellipsoidal-HMNPs@PDA-GQDs-FA), a dual-functional drug carrier, was stepwise constructed. The α -Fe 2 O 3 ellipsoidal nanoparticles were prepared by a hydrothermal method, and then coated with SiO 2 by Stöber method. The resulting core–shell structure, Fe 3 O 4 @SiO 2 @mSiO 2 -C 18 magnetic nano hollow spheres, abbreviated as HMNPs, was finally grafted with graphene quantum dots (GQDs), dopamine hydrochloride (PDA) and folic acid (FA) by amide reaction to obtain HMNPs@PDA-GQDs-FA. Transmission electron microscopy, Fourier transform infrared spectroscopy, fluorescence spectroscopy and element analysis proved the successful construction of the HMNPs@PDA-GQDs-FA nanoscale carrier-cargo composite. The carrier HMNPs@PDA-GQDs-FA has higher load (51.63 ± 1.53%) and release (38.56 ± 1.95%) capacity for gambogic acid (GA). Cytotoxicity test showed that the cell survival rate was above 95%, suggesting the cytotoxicity of the carrier-cargo was very low. The cell lethality (74.91 ± 1.2%) is greatly improved after loading GA because of the magnetic targeting of HMNPs, the targeting performance of FA to tumor cells, and the pH response to the surrounding environment of tumor cells of PDA. All results showed that HMNPs@PDA-GQDs-FA had good biocompatibility and could be used in the treatment of VX2 tumor cells after loading GA.