Metal–Organic‐Framework‐Derived Carbon Nanostructure Augmented Sonodynamic Cancer Therapy

TLDR

Sonodynamic therapy can overcome the depth‑penetration barrier of photo‑triggered modalities, yet discovering sonosensitizers with high efficacy and stability remains a major challenge. This study demonstrates the potential of a metal‑organic‑framework‑derived carbon nanostructure containing porphyrin‑like metal centers as an excellent sonosensitizer. The enhanced sonosensitization is attributed to the porphyrin‑like macrocycle’s large HOMO–LUMO gap that promotes reactive oxygen species production, and the nanoparticle‑assisted cavitation process was directly visualized by high‑speed imaging. Under ultrasound, the nanostructure generated high ROS levels, causing cellular destruction and achieving 85 % tumor inhibition, confirming structure‑dependent SDT enhancement.

Abstract

Abstract Sonodynamic therapy (SDT) can overcome the critical issue of depth‐penetration barrier of photo‐triggered therapeutic modalities. However, the discovery of sonosensitizers with high sonosensitization efficacy and good stability is still a significant challenge. In this study, the great potential of a metal–organic‐framework (MOF)‐derived carbon nanostructure that contains porphyrin‐like metal centers (PMCS) to act as an excellent sonosensitizer is identified. Excitingly, the superior sonosensitization effect of PMCS is believed to be closely linked to the porphyrin‐like macrocycle in MOF‐derived nanostructure in comparison to amorphous carbon nanospheres, due to their large highest occupied molecular orbital (HOMO)–lowest unoccupied molecular orbital (LUMO) gap for high reactive oxygen species (ROS) production. The nanoparticle‐assisted cavitation process, including the visualized formation of the cavitation bubbles and microjets, is also first captured by high‐speed camera. High ROS production in PMCS under ultrasound is validated by electron spin resonance and dye measurement, followed by cellular destruction and high tumor inhibition efficiency (85%). This knowledge is important from the perspective of understanding the structure‐dependent SDT enhancement of a MOF‐derived carbon nanostructure.