Preparation of fluorescent silica nanotubes and their application in gene delivery

The synthesis of fluorescent silica nanotubes with an inner diameter of hundreds of nanometer by sol-gel reaction using an anodic aluminum oxide (AAO) membrane as template and their application in gene delivery were discussed. It was found that a commercial AAO membrane with an average pore diameter of about 200 nm was employed as the template for silica nanotube preparation. The CdSe/ZnS core-shell nanocrystals with diameter of about 4 nm and 8 nm respectively were incorporated during nanotube preparation to generate green- and red-fluorescent silica nanotubes. Analysis suggest that the nanotube wall may act as a physical shield that protects the loaded DNA materials from potential environmental damage.