Preparation of redox-sensitive β-CD-based nanoparticles with controlled release of curcumin for improved therapeutic effect on liver cancer in vitro

A redox-sensitive beta-cyclodextrin nanoparticle (β-CD NP) system was prepared for the controlled release of curcumin (CUR), and its therapeutic efficacy on liver cancer was compared with that of CUR in vitro. 1-Dodecanethiol (DDT) was conjugated to per-6-thiol-β-CD by disulfide bond formation though an oxidation reaction (β-CD-ss-DDT). Rhodamine B (RhoB) was included into the β-CD-ss-DDT cavity by inclusion complex formation (β-CD-ss-DDT-ic-RhoB). CUR was encapsulated into β-CD-ss-DDT-ic-RhoB aggregates by self-assembly through dialysis method. The composition, morphology, size distribution and zeta potential of β-CD-ss-DDT-ic-RhoB NPs were characterized by proton nuclear magnetic resonance (¹H NMR), Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM) and dynamic light scattering (DLS), respectively. It was found that CUR was released from β-CD-ss-DDT-ic-RhoB/CUR NPs due to the dissociation of β-CD-ss-DDT through a reduction reaction. β-CD-ss-DDT-ic-RhoB/CUR NPs had a higher cellular uptake ratio and a greater anticancer effect on mouse hepatoma Hepa 1-6 cells than CUR, mainly attributed to the improved water-solubility of CUR after encapsulating it in the NPs. Our findings suggest that β-CD-ss-DDT-ic-RhoB NPs can be used as nanocarriers for delivering CUR into cancer cells, thereby serving as a clinical therapeutic agent for liver cancer treatment.