Mechanical Fabrication of Silver Cap onto Silica Nanotubes

We successfully synthesized Ag-capped SNTs using mechanical capping method and systematically investigated Ag cap fabrication under various conditions. The capping ability of Ag cap was evaluated using fluorescence dye release test and encapsulation of cargo molecules into SNT was also demonstrated. The results support that mechanical capping method can serve as a platform technique for the synthesis of multifunctional SNTs capped with various capping material by encapsulating functional cargo molecules. Template-synthesized silica nanotubes (SNTs) have proven to be an ideal multifunctional nanostructure for the biomedical applications such as drug delivery and bioseparation. Nano-tubes provide the advantage over nanospheres in that their inner voids can be used for loading large amounts of drug molecules and the differential functionalization of the inner and outer surfaces of SNTs enables appropriate surface modifications compatible with their environment. In addition, due to the tubular shape of nanotubes, the open end of SNTs can be capped to encapsulate cargo molecules and thus may control drug/gene uptake and release rate