pH-responsive mesoporous Fe₂O₃–Au nanomedicine delivery system with magnetic targeting for cancer therapy

Chemotherapy is the prime tool for the clinical treatment of cancer. The efficiency of treatment has been greatly improved with the assistance of nanomedicine delivery systems. However, it still meets the challenge of inefficient drug delivery and damage to normal tissues caused by uncontrolled drug release. Considering the various processes of nanomedicine acting on cancer cells, a pH-responsive mesoporous Fe₂O₃–Au nanomedicine delivery system with magnetic targeting was designed to achieve controlled drug release and improve the safety and efficiency. Fe₂O₃ particles were constructed with external mesopores and internal hollow structures, while Au nanoparticles were connected on the surface of Fe₂O₃ particles through pH-responsive valence bonds to encapsulate the drug. The Fe₂O₃–Au nanomedicine delivery system was equipped with magnetic targeting function, which could be induced by an external magnetic field to increase the drug concentration to kill cancer cells as well as reduce damage to normal cells. Meanwhile, based on the pH-responsive feature, the drug embedded could only be released in the weakly acidic condition of the cancer environment, while the nanomedicine delivery system remained closed in normal tissues. The Fe₂O₃–Au nanomedicine delivery system possessed the functions of pH responsiveness and magnetic targeting, enhancing safety and efficiency and providing a promising method for cancer therapy.