1. GNA-PEG-NLC and GNA-NLC were prepared by emulsification and low-temperature solidification methods. The optimized GNA-PEG-NLC and GNA-NLC were not only found to have small mean size (146.33 ± 2.11 and 144.07 ± 1.44) nm, high Zeta potential (-25.10 ± 1.35 and -28.03 ± 0.29) mV, but also great entrapment efficiency (79.07 ± 1.11 and 84.65 ± 0.98%). TEM proved that particles were nearly spherical with smooth surface shape. Furthermore, in vitro release revealed a burst release initially, followed by a sustained profiles up to 48 h, and the cumulative drug release of GNA-PEG-NLC and GNA-NLC was 65.90 ± 2.34% and 69.25 ± 1.77%, respectively. 2. In pharmacokinetic, GNA-PEG-NLC exhibited prolonged MRT and higher AUC values compared with GNA-NLC and GNA solution. Moreover, the tissue distribution demonstrated a high uptake of GNA-PEG-NLC in stomach. 3. These results indicated that PEG-NLC is a promising delivery system for GNA, which could prolong drug circulation time in body and thus improved its bioavailability.
Keywords: Bioavailability; PEG-modified nanostructured lipid carriers; gambogenic acid.