Light-Addressable and Degradable Silica Capsules for Delivery of Molecular Cargo to the Cytosol of Cells

Degradable and light-addressable silica capsules have been prepared on the basis of CaCO3 template particles. It was possible to load these capsules with an array of molecules such as anticancer drugs (doxorubicin), proteins (bovine serum albumin), and nucleic acids (mRNA encoding green fluorescent protein). In vitro degradation and release of these molecules was demonstrated and quantitatively compared with several kinds of polyelectrolyte multilayer capsules as examples of other delivery vehicles. The data suggests hydrolysis as a mechanism involved in intracellular degradation of silica capsules. Photothermal heating (by integrating plasmonic nanoparticles in the silica shell) was further used to induce remote molecular release.