Characterization and biodistribution in vivo of quercetin-loaded cationic nanostructured lipid carriers

Nanobiotechnology has been recently viewed as a promising strategy to improve therapy efficacy by promoting the accumulation of hydrophobic bioactive compounds in tissues. The aim of present study was to formulate a novel quercetin-loaded cationic nanostructured lipid carriers (QR-CNLC) and to evaluate its biodistribution in vivo after oral administration. QR-CNLC were prepared by emulsifying at high temperature and subsequent solidifying at low temperature using various functional ingredients, and its characteristics, including physical index, release profile in vitro, and tissue distribution in vivo, were investigated. The results demonstrated that QR-CNLC exhibited an average particle size 126.6 nm, a zeta potential of 40.5 mV and 89.3% entrapment efficiency. QR-CNLC performed slower release compared with quercetin solution in vitro. QR-CNLC showed higher AUC (area under tissue concentration–time curve) value and higher Cmax value in lung, liver and kidney compared with control group. The value of relative intake rate (re) for lung, liver and kidney was 1.57, 1.51 and 1.68, respectively, which revealed that quercetin can be significantly accumulated in lung, kidney and liver after oral administration of QR-CNLC compared with quercetin suspension. In conclusion, cationic nanostructured lipid carriers may be an attractive nanocarrier system for oral delivery of hydrophobic functional components.