Packing-accelerated consecutive NIR excitation (PACE) enables high energy photocatalysis and antitumor immunity in vivo.

Packing-accelerated consecutive excitation (PACE) enables high-energy photocatalysis and tumor regression using low-energy NIR photons in vivo.

• Why it matters: Overcoming the limitations of insufficient photon energy and rapid charge recombination in NIR photocatalysis is crucial for deep-tissue biomedical applications and effective cancer treatments.
• What they did: A self-assembling ruthenium complex, Ru-3, was designed to form nanoaggregates with aggregation-stabilized excited states, enabling dual NIR-I/IIa irradiation to facilitate consecutive photon harvesting and high-energy reactions.
• The result: This approach achieved efficient oxidation of mitochondrial NADH, induced tumor cell pyroptosis, reprogrammed immune cells, and resulted in tumor regression with minimal toxicity, establishing a new paradigm for biological photocatalysis.