Plasmonic nano-dumbbells for enhanced photothermal and photodynamic synergistic damage of cancer cells

摘要： The longitudinal surface plasmon resonance of light-irradiated gold nanorods (Au NRs) is generated to enhance the local electric ?elds of Au NR-based nano-dumbbells (NDs), tailored speci?cally by coating mesoporous silica at two poles of Au NRs and embedding photosensitizer indocyanine green (ICG) into the mesopores. The assembled NDs possess a superior uniformity and water dispersity with a strong plasmonic absorption around 800 nm. Time-domain ?nite-difference calculations indicate that the enhanced local electric ?eld of NDs is predominantly distributed in the dumbbells at two poles of Au NRs, which improves the photonic performance of ICG signi?cantly. Illuminated by an 800 nm laser, the fabricated NDs demonstrate an enhanced combination of photothermal and photodynamic effects in comparison to either Au NRs or ICG alone. Synergistic damaging of photothermal and photodynamic combination to nasopharyngeal carcinoma cells has been corroborated experimentally, thus causing substantial cell death under a lower incident near-infrared laser power. This study concludes that the plasmonic NDs combined synergistically with ef?cient photothermal and photodynamic effects are highly promising in cancer therapy.