Preparation,characterization, cellular uptake and evaluation in vivo of solid lipid nanoparticles loaded with cucurbitacin B

In this work, solid lipid nanoparticles loaded with cucurbitacin B (Cu B-SLNs) were prepared. It was found that the concentration of poloxamer 188 and soybean lecithin had effects on the mean particle size and size distribution. The zeta potentials were around ?33 mV. In vitro release studies showed a sustained release after a burst release. Internalization of Cu B into HepG2 cells could be enhanced by the encapsulation of SLN matrix. The IC50 values of Cu B-SLNs were lower than that of Cu B solution. Both free Cu B and Cu B-SLNs had effectively inhibited the tumor growth and displayed a dose-dependent anti-tumor efficacy. Cu B-SLNs at a dose of 0.11?mg/kg produced the greatest anti-tumor effects (53.3%), which was significant higher than Cu B solution (31.5%, p < 0.05). Cu B-SLNs showed a longer MRT in vivo. The AUC of Cu B-SLNs for tumor increased 3.5 –fold when compared to Cu B solution. The targeting efficiency of Cu B-SLNs was 1.94 times higher in liver as compared to that of Cu B solution. These results indicated that Cu-B SLNs could passively target the tumor with EPR effect, improve the therapeutic efficacy of Cu B, and reduce the doses.