Pellets of phospholipids and d-glucose with improved intestinal absorption and oral bioavailability of salvianolic acid B

Salvianolic acid B (SAB) is a widely used cardioprotective agent, while its clinical application was limited by poor intestinal absorption and low oral bioavailability. In this study, SAB phospholipid (SP) complex was first prepared to improve the lipophilicity of SAB and then combined with d-glucose to further enhance intestinal absorption. Compared with free SAB, SP or the mixture of SAB and d-glucose, combination of SP and d-glucose showed higher intestinal absorption evidenced by increased effective permeation coefficient (P_eff) in the in situ single-pass intestinal perfusion (SPIP) assay. Subsequently, SP and d-glucose at mass ratio of 1:6, with the highest P_eff of SAB, were chosen for the preparation of complexed pellets to improve oral absorption efficiency of SAB. As expected, the obtained pellets significantly enhanced oral bioavailability of SAB in the pharmacokinetic study characterized by increasing C_max and AUC_0-t of SAB by 14.88-fold and 5.02-fold than free SAB, respectively. In conclusion, combination of d-glucose in SP pellets can effectively improve the intestinal absorption and oral bioavailability of SAB.