Pollen-like silica nanoparticles as a nanocarrier for tumor targeted and pH-responsive drug delivery

Aptamer modified hollow silica nanoparticles with pollen structure ([email protected]) were synthesized and used as a nanocarrier for tumor targeted and pH-responsive drug delivery. The 292 ± 14 nm interior void in diameter together with 11.8 nm surface pore size of [email protected] nanoparticles contributed to a high drug loading efficiency of 0.509 g g−1. Furthermore, the drug delivery system was pH-responsive, and the releasing efficiency was up to 87.5% at pH of 5. The special spikes of this [email protected] nanoparticles acted as “entry claws” to enhanced the interaction between cell and drug nanocarriers and then increased the internalization rate of drug vehicles. The cell uptake assay suggested that most of doxorubicin (DOX)@[email protected] nanoparticles can escape form lysosome and located in nuclei of MCF-7 cells. The targeted performance testing showed that almost no [email protected]@aptamer were internalized by normal cells, indicating a high specificity of our drug vehicles. The cytotoxicity of nanoparticles was also investigated, the [email protected] particles had excellent biocompatibility and the cell viability was nearly 100%. After loaded with DOX, [email protected]@aptamer showed great potential in targeted therapy of tumors, and only 4.2% MCF-7 cells were viable.