Synthesis of nanostructured calcium carbonate/methotrexate@silica and its application in cancer therapy

Abstract

Biomedical applications of nontoxic amorphous calcium carbonate (ACC) have mainly been restricted because of its aqueous instability. Herein, we report the successful synthesis of highly stable ACC–methotrexate (MTX)@SiO₂ nanospheres in vitro for use in cancer therapy. Further, vaterite–MTX@SiO₂ nanospheres were also prepared for comparison. In our synthesis procedure, ACC–MTX and vaterite–MTX were firstly prepared at different pH values, and then SiO₂ layers were subsequently deposited by the well-known Stöber method. The results indicated that the special structure of ACC–MTX@SiO₂ presents better controlled-release and results in efficient death of cancer cells, thus showing its great potential as a desirable chemotherapeutic system for cancer therapy.