Aminated β-cyclodextrin-grafted Fe3O4-loaded gambogic acid magnetic nanoparticles: preparation, characterization, and biological evaluation

Abstract

Based on aminated β-cyclodextrin (6-NH₂-β-CD)-grafted Fe₃O₄ and gambogic acid (GA) clathrate complexes, a nanoparticle delivery system was developed with the aim to achieve low irritation, strong targeting, and high bioavailability of a gambogic acid magnetic nanopreparation. 6-NH₂-β-CD grafted onto Fe₃O₄ MNPs was demonstrated by high-resolution transmission electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, zeta potential, and magnetic measurements. The average particle size of the Fe₃O₄@NH₂-β-CD MNPs was 147.4 ± 0.28 nm and the PDI was 0.072 ± 0.013. The encapsulation efficiency, drug loading, zeta potential, and magnetic saturation values of the Fe₃O₄@NH₂-β-CD MNPs were 85.71 ± 3.47%, 4.63 ± 0.04%, −29.3 ± 0.42 mV, and 46.68 emu g⁻¹, respectively. Compared with free GA, the in vitro release profile of GA from Fe₃O₄@NH₂-β-CD MNPs was characterized by two phases: an initial fast release and a delayed-release phase. The Fe₃O₄@NH₂-β-CD MNPs displayed continuously increased cytotoxicity against HL-60 and HepG2 cell lines in 24 h, whereas the carrier Fe₃O₄@NH₂-β-CD MNPs showed almost no cytotoxicity, indicating that the release of GA from the nanoparticles had a sustained profile and Fe₃O₄@NH₂-β-CD MNPs as a tumor tissue-targeted drug delivery system have great potential. Besides, blood vessel irritation tests suggested that the vascular irritation could be reduced by the use of Fe₃O₄@NH₂-β-CD MNPs encapsulation for GA. The t_1/2 and the AUC of the Fe₃O₄@NH₂-β-CD@GA MNPs were found to be higher than those for the GA solution by approximately 2.71-fold and 2.42-fold in a pharmacokinetic study, respectively. The better biocompatibility and the combined properties of specific targeting and complexation ability with hydrophobic drugs make the Fe₃O₄@NH₂-β-CD MNPs an exciting prospect for the targeted delivery of GA.