Silica-based vectors are attractive as gene transfer vehicles due to their high stability, safety, and ease of structural and surface modification. A variety of silica-based vectors for gene delivery have been reported, including silica nanotubes (SNT), silica sheets, and silica NPs (solid (non-porous) silica NPs and porous silica NPs). Among these, silica NPs have been extensively investigated by researchers as carriers with many useful and attractive properties.
Several reports have been published on the use of silica NPs in nucleic acid delivery. Typically, nucleic acid molecules are loaded into silica NPs through weak non-covalent interactions. The size of the pores and the degree of surface functionalization play a crucial role in the loading and nucleic acid release rate. The addition of different types of cationic macromolecules, including PEIs, dendrimers, and lipids, has been used to modify the surface of silica NPs for the adsorption and delivery of nucleic acids.
