METHODS: A nanosuspension was prepared using high pressure homogenization (HPH) techniques. The physico-chemical properties of the kaempferol nanosuspension (KNS) were characterized using photon correlation spectroscopy (PCS), transmission electron microscope (TEM), Fourier transform infrared spectroscopy (FTIR) and x-ray diffractometry (XRD). A reversephase high performance liquid chromatography (RP-HPLC) method for the analysis of the drug in rat plasma was developed and validated as per ICH guidelines. In vivo pharmacokinetic parameters of oral pure kaempferol solution, oral kaempferol nanosuspension and intravenous pure kaempferol were assessed in rats.

RESULTS AND DISCUSSION: The kaempferol nanosuspension had a greatly reduced particle size (426.3 ± 5.8 nm), compared to that of pure kaempferol (1737 ± 129 nm). The nanosuspension was stable under refrigerated conditions. No changes in physico-chemical characteristics were observed. In comparison to pure kaempferol, kaempferol nanosuspension exhibited a significantly (P<0.05) increased in Cmax and AUC(0-∞) following oral administration and a significant improvement in absolute bioavailability (38.17%) compared with 13.03% for pure kaempferol.

METHOD: Therefore, there is a need to improve delivery of therapeutic macromolecules to enable non-invasive delivery routes, less frequent dosing through controlled-release drug delivery, and improved drug targeting to increase efficacy and reduce side effects.

RESULT: Non-invasive administration routes such as intranasal, pulmonary, transdermal, ocular and oral delivery have been attempted intensively by formulating macromolecules into nanoparticulate carriers system such as polymeric and lipidic nanoparticles.