Targeted delivery and pH-responsive release of doxorubicin to cancer cells using calcium carbonate/hyaluronate/glutamate mesoporous hollow spheres

Currently, the efficacies of the existing anticancer drugs used in chemotherapy are still unsatisfactory. Therefore, drug delivery system has received considerable research interest. In the present study, calcium carbonate/hyaluronate/glutamate mesoporous hollow spheres are prepared through a facile method. The results indicate that the mesoporous hollow spheres can efficiently load the anticancer drug doxorubicin. Through the specific binding of hyaluronate on hollow spheres with CD44 receptors overexpressed on cancer cells, the drug-loaded hollow spheres can be specifically delivered to target cancer cells. Owing to the gradually dissolution of calcium carbonate in the weak acidic microenvironment of cancer cells, the loaded doxorubicin can be released over the period of 14days with pH-responsive and sustained manner to specifically and significantly treat cancers. Through loaded onto the hollow spheres, the IC50 value of doxorubicin for HeLa cancer cells is 0.0113μg/mL, much lower than that of the free doxorubicin (0.0801μg/mL). However, the IC50 value of doxorubicin for V79-4 cells is 0.2032μg/mL, obviously higher than that of the free DOX (0.1396μg/mL). The specificity of the doxorubicin between normal and cancer cells can be enhanced about 10-fold. The current study suggests the possible application of pH-responsive inorganic carriers for efficiently treatment of human cancers.