Abstract
Quercetin-loaded nanosuspensions (Que-NSps) added metabolic inhibitors were evaluated as drug delivery system to promote the oral bioavailability of quercetin. Que-NSps were prepared respectively using d-alpha tocopherol acid polyethylene glycol succinate (TPGS) or Soybean Lecithin (SPC) as stabilizer. On the basis, Piperine (Pip) or sodium oleate (SO) was, respectively, encapsulated in Que-NSps as phase II metabolic inhibitors. The resulting Que-NSps all displayed a mean particle size of about 200 nm and drug loading content was in the range of 22.3–27.8%. The release of quercetin from Que-NSps was slow and sustained. After oral administration of 50 mg/kg different Que-NSps, the levels of free quercetin in plasma were significantly promoted, the concentration of quercetin metabolites (isorhamnetin and quercetin 3-O-β-d-Glucuronide) were decreased. The absolute bioavailability was, respectively 15.55%, 6.93%, 12.38%, and 23.58% for TPGS-Que-NSps, TPGS-SO-Que-NSps, SPC-Que-NSps, and SPC-Pip-Que-NSps, and 3.61% for quercetin water suspension. SPC-Pip-Que-NSps turned out to an ideal nanocarrier combined nano drug delivery system together with metabolic inhibitor to promote oral absorption of quercetin.
Disclosure statement
The author reports no conflicts of interest in this work.