Alkaline media‐sensitive nanocarrier based on carboxylated cyclodextrin for targeted delivery of anti‐colon drug.

The pH‐responsive nanoparticles are a promising drug‐carrier because they always showed sensitivity and specificity to the pH changes caused by the surrounding environment. Most of the therapeutic drugs are generally absorbed in the stomach and small intestine due to the pH‐responsive nanoparticles always release the cargos at acidic media, making them difficult to reach the lower part of the large intestine, as well as inhibiting the therapeutic effects. Herein, an alkaline media‐sensitive supramolecular nanoparticle, regarded as SACD/PEI NPs, is prepared. SACD/PEI NPs exhibit assemble/disassemble state by changing the pH, which is used to encapsulate the anti‐colon drug CSL. CSL@SACD/PEI NPs showed a high release rate of 86.1% for the encapsulated CSL at pH = 8.5 (mimic the colon micro‐environment), while keeping stable at pH = 1.2 (mimic the gastric acid micro‐environment). Meanwhile, CSL@SACD/PEI NPs exhibited low hemolysis, indicating they possess good biocompatibility. In cell experiments, CSL@SACD/PEI NPs had a similar inhibitory effect on colon tumor cell SW480 and showed low cytotoxicity to normal cells compared with free CSL. Furthermore, both free CSL and CSL@SACD/PEI NPs showed excellent apoptosis effects on tumor cell SMMC‐7721. We hope that CSL@SACD/PEI NPs could be the valuable base‐answered drug delivery candidate, and have potential application for colon tumor therapy. [ABSTRACT FROM AUTHOR]