• upconversion;
  • nanomaterials;
  • NIR-triggered release;
  • caged nitric oxides;
  • photoactivation
Thumbnail image of graphical abstract

NO is a key vasodilator in mammalian cardiovascular systems and has been shown to sensitize tissue to γ-radiation. However, photochemical NO precursors that can be activated by these NIR wavelengths are extremely limited. G. D. Stucky, D. Zhao, P. C. Ford, F. Zhang and co-workers have addressed this issue by utilizing the known NIR to visible upconversion properties of lanthanide-doped NaYF4 nanocrystals. This result, described on page 3800, is a potential game changer in multiphoton excitation-based therapeutic delivery of NO and other small molecule bioregulators to physiological targets.