Preparation of icariside II-phospholipid complex and its absorption across Caco-2 cell monolayers

In the present study, an icariside II-phospholipid complex was prepared, and its physicochemical properties including UV spectrum, IR spectrum, differential scanning calorimetry (DSC) were tested. Furthermore, the absorption of icariside II and icariside II–phospholipid complex was compared in a Caco-2 cell culture model. The results show that icariside II–phospholipid complex could significantly increase the A-B transport of icariside II (P < 0.01), with A-B Papp of (3.92 ± 0.50) × 10^–6cm/s compared to control (2.05 ± 0.18) × 10^–6cm/s (increased by 91%). Likewise, the B-A transport of icariside II was significantly enhanced (P < 0.01), with Papp of (15.3 ± 0.72) × 10^–6cm/s (control) to (22.4 ± 1.4) × 10^–6cm/s (46% increase). Efflux ratio of icariside II decreased by 23.5% after forming icariside II–phospholipid complex. The therefore, it could be concluded that phospholipid complexation can increase the intestinal absorption of icariside II.