pH-sensitive magnetic drug delivery system via layer-by-layer self-assembly of CS/PEG and its controlled release of...

Cancer is one of the biggest killers threat to human life and health and is still difficult to treat mainly due to the lack of targeted drug delivery stages and limitations associated with delivering drugs to targeted cancer tissues. The goal of this work was to develop a magnetic, pH-sensitive formulation for targeted delivery of chemotherapeutic agents to cancer cells. Then the functional drug delivery system (Fe₃O₄@CS/PEG-DOX) was synthesized by the layer-by-layer (LbL) self-assembly technique. And the drug loading content is calculated to be 19.1%. In addition, the Fe₃O₄@CS/PEG-DOX exhibited excellent pH-sensitivity, 73.1% DOX was released within 48 h at pH 4.0. Furthermore, all the release behaviors fit the Higuchi model very well and the dissolution of CS/PEG layers played a key role on DOX release from Fe₃O₄@CS/PEG-DOX. The results of toxicity analysis in human liver hepatocellular carcinoma cells (HepG2) revealed that Fe₃O₄@CS/PEG-DOX exhibited high anti-tumor activity, while the Fe₃O₄@CS/PEG nanocomposites were practically non-toxic. Therefore, all the results demonstrated that the Fe₃O₄@CS/PEG-DOX could have an important impact on the development of targeted intracellular delivery nanodevices for cancer therapy.