Immuno Gold Nanocages with Tailored Optical Properties for Targeted Photothermal Destruction of Cancer Cells

TLDR

Gold nanocages (~45 nm) have been engineered to strongly absorb near‑infrared light for photothermal cancer therapy. The nanocages were functionalized with anti‑HER2 antibodies to target EGFR‑overexpressing SK‑BR‑3 breast cancer cells, enabling strong NIR absorption for photothermal therapy. Numerical simulations show a large absorption cross section (3.48 × 10⁻¹⁴ m²), and preliminary experiments demonstrate that 1.5 W/cm² of NIR light induces thermal cell death with damage area increasing linearly up to 4.7 W/cm², indicating that immuno gold nanocages could be an effective photothermal cancer therapy.

Abstract

Gold nanocages with a relatively small size (e.g., ∼45 nm in edge length) have been developed, and the structure of these nanocages was tailored to achieve strong absorption in the near-infrared (NIR) region for photothermal cancer treatment. Numerical calculations show that the nanocage has a large absorption cross section of 3.48 × 10-14 m2, facilitating conversion of NIR irradiation into heat. The gold nanocages were conjugated with monoclonal antibodies (anti-HER2) to target epidermal growth factor receptors (EGFR) that are overexpressed on the surface of breast cancer cells (SK-BR-3). Our preliminary photothermal results show that the nanocages strongly absorb light in the NIR region with an intensity threshold of 1.5 W/cm2 to induce thermal destruction to the cancer cells. In the intensity range of 1.5−4.7 W/cm2, the circular area of damaged cells increased linearly with the irradiation power density. These results suggest that this new class of bioconjugated gold nanostructures, immuno gold nanocages, can potentially serve as an effective photothermal therapeutic agent for cancer treatment.