Near-infrared light-activated cancer cell targeting and drug delivery with aptamer-modified nanostructures

Stimuli-activated targeted delivery systems for highly accurate treatment of tumors have received considerable attention in recent years. Herein, we reveal a light-activable cancer-targeting strategy that uses a complementary DNA sequence to hybridize and mask sgc8 aptamers conjugated onto photothermal agents such as gold nanorods or single-walled carbon nanotubes (SWNTs). Upon exposure to near-infrared (NIR) laser, localized photothermal heating of the surface of those nano-agents results in dehybridization of the double-stranded DNA and uncaging of the aptamer sequence to allow specific cancer-cell targeting. Utilizing doxorubicin-loaded SWNTs as a model system, targeted drug delivery to cancer cells activated by NIR light was achieved. This work demonstrates the concept of NIR-activable tumor-targeting delivery systems with controllable cancer-cell binding to potentially enable highly specific and efficient cancer therapy.