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 14 days 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 0.0113 μg/mL, much lower than that of the free doxorubicin (0.0801 μg/mL). However, the IC50 value of doxorubicin for V79-4 cells is 0.2032 μg/mL, obviously higher than that of the free DOX (0.1396 μg/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.Herein, calcium carbonate/hyaluronate/glutamate mesoporous hollow spheres were prepared and used for targeted delivery and pH-sensitive release of anticancer drugs to treat human cancers.Download high-res image (123KB)Download full-size image

Hollow silica nanospheres coated with biocompatible and pH-sensitive inorganic insoluble calcium salts including calcium carbonate and hydroxyapatite have been successfully prepared. The results indicate that the nanospheres can efficiently load doxorubicin and release it in a pH-responsive and sustained manner, and improve the treatment efficacy significantly.

Hollow silica nanospheres coated with biocompatible and pH-sensitive inorganic insoluble calcium salts including calcium carbonate and hydroxyapatite have been successfully prepared. The results indicate that the nanospheres can efficiently load doxorubicin and release it in a pH-responsive and sustained manner, and improve the treatment efficacy significantly.