Gold nanostructures for cancer imaging and therapy

Gold nanostructures can manipulate light at the nanoscale based on the optical phenomenon widely known as localized surface plasmon resonance (LSPR). Upon light excitation, specific gold nanostructures are supposed to preferentially absorb or scatter light in the near-infrared (NIR) region, which enable them applicable as imaging and therapeutic agents. Furthermore, facile surface functionaliza-tion via Au-S bonding makes gold nanostructures as universal substrates to attach functional molecules, drug cargo, and targeting ligands. Together with their easy synthesis and non-toxicity, gold nanostructures have emerged as a greatly promising platform in cancer diagnostics and treatment. This chapter summarizes the progress made in cancer imaging and therapy with gold nanostructures (1) as therapeutic components for photothermal therapy, photodynamic therapy, chemotherapy, and their combination; (2) as probes for various imaging techniques including dark-field, optical coherence tomography, two-photon luminescence, photoacoustic imaging, computed tomography, and surface-enhanced Raman scattering based imaging; and (3) as a theranostic platform for imaging-guided therapy. © Springer-Verlag Berlin Heidelberg 2016.