Enhanced type I photoreaction of indocyanine green via electrostatic-force-driven aggregation

Nanoscale. 2020 May 7;12(17):9517-9523. doi: 10.1039/d0nr01208d.

Abstract

Owing to the strong NIR absorbance, indocyanine green (ICG) has attracted new attention in emerging photo-theranostics. However, ICG has a very low ROS production efficiency and mainly works through the type II photoreaction via its monomer. The aggregation tendency of ICG in aqueous milieus further worsens the scenario. Herein, ICG aggregates show an enhanced type I photoreaction pathway and have much better photooxidizing capability than its monomer, which improves the performance of ICG in the photodynamic inactivation of bacteria. This finding provides a feasible way to tackle the contradiction of ROS generation and ICG aggregation. Finally, the photodynamic effect of ICG aggregates was combined with the photothermal effect of gold nanorods to achieve an effective treatment of bacterial infection.

MeSH terms

  • Animals
  • Cell Line
  • Gold / chemistry
  • Gold / therapeutic use
  • Humans
  • Indocyanine Green / chemistry*
  • Indocyanine Green / therapeutic use
  • Mice
  • Nanoparticles / chemistry*
  • Nanoparticles / therapeutic use
  • Oxidation-Reduction
  • Photolysis
  • Photosensitizing Agents / chemistry*
  • Photosensitizing Agents / therapeutic use
  • Phototherapy
  • Reactive Oxygen Species / chemistry
  • Reactive Oxygen Species / pharmacology
  • Staphylococcal Infections / therapy
  • Staphylococcus aureus / drug effects
  • Static Electricity

Substances

  • Photosensitizing Agents
  • Reactive Oxygen Species
  • Gold
  • Indocyanine Green