Two-photon excitation nanoparticles for photodynamic therapy

Chem Soc Rev. 2016 Dec 21;45(24):6725-6741. doi: 10.1039/c6cs00442c. Epub 2016 Oct 5.


Two-photon excitation (TPE) nanoparticle-based photosensitizers (PSs) that combine the advantages of TPE and nanotechnology have emerged as attractive therapeutic agents for near-infrared red (NIR) light excited photodynamic therapy (PDT) for cancer treatment. TPE PDT is characterized by nonlinear absorption of two relatively low-energy photons of NIR light with the resulting emission of high-energy visible light. This high-energy light can sensitize oxygen to produce cytotoxic reactive oxygen species (ROS) and singlet oxygen (1O2) which can kill cancer cells. The long-wavelength light used to excite TPE NPs allows for deeper tissue penetration to achieve efficient PDT of deep-seated tumors. Moreover, TPE nanoparticles normally have large two-photon absorption (TPA) cross-sections, which hold great potential as efficient two-photon donors in PDT. In this review, we will summarize the recent advances made in the development of TPE nanoparticles for cancer PDT. Five different TPE nanoparticles, including quantum dots (QDs), carbon nanomaterials, silica nanoparticles, gold nanomaterials, and polymer nanoparticles, are summarized in detail, and the existing challenges as well as the future perspectives are also discussed.

Publication types

  • Review

MeSH terms

  • Animals
  • Carbon / chemistry
  • Gold / chemistry
  • Humans
  • Light
  • Metal Nanoparticles / chemistry
  • Nanoparticles / chemistry*
  • Neoplasms / drug therapy
  • Photochemotherapy / methods*
  • Photosensitizing Agents / chemistry*
  • Photosensitizing Agents / therapeutic use
  • Polymers / chemistry
  • Silicon Dioxide / chemistry


  • Photosensitizing Agents
  • Polymers
  • Carbon
  • Gold
  • Silicon Dioxide