Notice of Retraction Novel Norcantharidin-Loaded Liver Targeting Chitosan Nanoparticles to Enhance Intestinal Absorption

In this paper, two novel liver-targeting nanoparticles, norcantharidin-loaded chitosan nanoparticles (NCTD-CS-NPs) and norcantharidin -associated galactosylated chitosan nanoparticles (NCTD -GC-NPs), were prepared using ionic cross-linkage. To investigate the intestinal absorption mechanisms of the two preparations, a series of experiments was carried out, including in situ circulation method, in vitro everted gut sacs, and Using chamber perfusion technique. The absorption rate constants (Ka) of NCTD at different segments were duodenum>;jejunum>;ileum>;colon. The concentration had no distinctive effect on absorption kinetics, suggesting that drug absorption is not dose-dependent. The transport of NCTD was found to be inhibited by P-glycoprotein (P-gp) inhibitor, indicating that NCTD might be the substrate of P-gp. The order of the absorption enhancer effects were as follows: low molecular weight chitosan (CS-8kDa) >; high molecular weight chitosan (CS-30KDa) >; Poloxamer >; sodium dodecyl sulfate (SDS) >; Sodium deoxycholate (SDCh). The results indicate that the chitosan nanoparticles can improve intestinal absorption of NCTD.