TfR Aptamer-Functionalized MSNs for Enhancing Targeted Cellular Uptake and Therapy of Cancer Cells

Mesoporous silica nanoparticles (MSNs), as novel nanocarriers for drug delivery in cancer treatment, have attracted widespread concern because of their rich pore structure, large pore capacity, ease of modification, and biocompatibility. However, the limitation of nontargeting and low uptake efficiency hindered their further application. Considering the overexpression of the transferrin receptor (TfR) on most cancer cell membranes, herein, we propose a strategy to effectively enhance the cellular internalization of MSNs by arming them with the TfR aptamer. Cellular fluorescent imaging and flow cytometry analysis demonstrated that TfR aptamer-functionalized MSNs exhibited superior cellular internalization compared to unmodified or random sequence-modified MSNs toward three different cancer cell lines, including MCF-7, HeLa, and A549. Furthermore, TfR aptamer-functionalized MSNs displayed enhanced drug delivery efficiency compared with MSNs at equivalent doses and incubation times. These results suggested that TfR aptamer-functionalized MSNs have the potential for enhanced delivery of therapeutic agents into TfR-positive cancer cells to improve therapeutic efficacy.