This invited paper is part of the Series: Applications of Imaging to Biological and Photobiological Systems.
Gold Nanorods as Contrast Agents for Biological Imaging: Optical Properties, Surface Conjugation and Photothermal Effects†
Article first published online: 16 JAN 2009
© 2009 The Authors. Journal Compilation. The American Society of Photobiology
Photochemistry and Photobiology
Volume 85, Issue 1, pages 21–32, January/February 2009
How to Cite
Tong, L., Wei, Q., Wei, A. and Cheng, J.-X. (2009), Gold Nanorods as Contrast Agents for Biological Imaging: Optical Properties, Surface Conjugation and Photothermal Effects. Photochemistry and Photobiology, 85: 21–32. doi: 10.1111/j.1751-1097.2008.00507.x
- Issue published online: 16 JAN 2009
- Article first published online: 16 JAN 2009
- Received 23 September 2008, accepted 23 October 2008
Gold nanorods (NRs) have plasmon-resonant absorption and scattering in the near-infrared (NIR) region, making them attractive probes for in vitro and in vivo imaging. In the cellular environment, NRs can provide scattering contrast for darkfield microscopy, or emit a strong two-photon luminescence due to plasmon-enhanced two-photon absorption. NRs have also been employed in biomedical imaging modalities such as optical coherence tomography or photoacoustic tomography. Careful control over surface chemistry enhances the capacity of NRs as biological imaging agents by enabling cell-specific targeting, and by increasing their dispersion stability and circulation lifetimes. NRs can also efficiently convert optical energy into heat, and inflict localized damage to tumor cells. Laser-induced heating of NRs can disrupt cell membrane integrity and homeostasis, resulting in Ca2+ influx and the depolymerization of the intracellular actin network. The combination of plasmon-resonant optical properties, intense local photothermal effects and robust surface chemistry render gold NRs as promising theragnostic agents.