Gold Nanocages for Biomedical Applications


  • This work was supported in part by a Director's Pioneer Award (5DP1OD000798-Y.X.) and a grant (R01-CA120480-X.D.L.) from NIH, a grant (DMR-0451788-Y.X.) and Career Award (X.D.L.) from NSF, a fellowship from David and Lucile Packard Foundation (Y.X.), and a DARPA-DURINT subcontract from Harvard University (Y.X.). Y.X. is an Alfred P. Sloan Research Fellow (2000–2005) and a Camille Dreyfus Teacher Scholar (2002–2007). L.A. thanks the Center for Nanotechnology at UW for an IGERT Student Fellowship jointly sponsored by NSF and NCI. Part of the work was performed at the Nanotech User Facility (NTUF) of the UW Center for Nanotechnology, a member of the National Nanotechnology Infrastructure Network (NNIN) funded by NSF.


Nanostructured materials provide a promising platform for early cancer detection and treatment. Here we highlight recent advances in the synthesis and use of Au nanocages for such biomedical applications. Gold nanocages represent a novel class of nanostructures, which can be prepared via a remarkably simple route based on the galvanic replacement reaction between Ag nanocubes and HAuCl4. The Au nanocages have a tunable surface plasmon resonance peak that extends into the near-infrared, where the optical attenuation caused by blood and soft tissue is essentially negligible. They are also biocompatible and present a well-established surface for easy functionalization. We have tailored the scattering and absorption cross-sections of Au nanocages for use in optical coherence tomography and photothermal treatment, respectively. Our preliminary studies show greatly improved spectroscopic image contrast for tissue phantoms containing Au nanocages. Our most recent results also demonstrate the photothermal destruction of breast cancer cells in vitro by using immuno-targeted Au nanocages as an effective photo-thermal transducer. These experiments suggest that Au nanocages may be a new class of nanometer-sized agents for cancer diagnosis and therapy.