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Abstract Although sonodynamic therapy (SDT) has shown promise for cancer treatment, the lack of efficient sonosensitizers (SSs) has limited the clinical application of SDT. Here, a new strategy is reported for designing efficient nano‐sonosensitizers based on 2D nanoscale metal–organic layers (MOLs). Composed of Hf‐oxo secondary building units (SBUs) and iridium‐based linkers, the MOL is anchored with 5,10,15,20‐tetra(p‐benzoato)porphyrin (TBP) sensitizers on the SBUs to afford TBP@MOL. TBP@MOL shows 14.1‐ and 7.4‐fold higher singlet oxygen (1O2) generation than free TBP ligands and Hf‐TBP, a 3D nanoscale metal–organic framework, respectively. The1O2generation of TBP@MOL is enhanced by isolating TBP SSs on the SBUs of the MOL, which prevents aggregation‐induced quenching of the excited sensitizers, and by triplet–triplet Dexter energy transfer between excited iridium‐based linkers and TBP SSs, which more efficiently harnesses broad‐spectrum sonoluminescence. Anchoring TBP on the MOL surface also enhances the energy transfer between the excited sensitizer and ground‐state triplet oxygen to increase1O2generation efficacy. In mouse models of colorectal and breast cancer, TBP@MOL demonstrates significantly higher SDT efficacy than Hf‐TBP and TBP. This work uncovers a new strategy to design effective nano‐sonosensitizers by facilitating energy transfer to efficiently capture broad‐spectrum sonoluminescence and enhance1O2generation.
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Triarylboron‐Doped Acenethiophenes as Organic Sonosensitizers for Highly Efficient Sonodynamic Therapy with Low Phototoxicity
Abstract The development of efficient organic sonosensitizers is crucial for sonodynamic therapy (SDT) in the field of cancer treatment. Herein, a new strategy for the development of efficient organic sonosensitizers based on triarylboron‐doped acenethiophene scaffolds is presented. The attachment of boron to the linear acenethiophenes lowers the lowest unoccupied molecular orbital (LUMO) energy, resulting in redshifted absorptions and emissions. After encapsulation with the amphiphilic polymer DSPE‐mPEG2000, it is found that the nanostructured BAnTh‐NPs and BTeTh‐NPs (nanoparticles of BAnTh and BTeTh) shows efficient hydroxyl radical (•OH) generation under ultrasound (US) irradiation in aqueous solution with almost no phototoxicity, which can overcome the shortcomings of O2‐dependent SDT and avoid the potential cutaneous phototoxicity issue. In vitro and in vivo therapeutic results validate that boron‐doped acenethiophenes as sonosensitizers enable high SDT efficiency with low phototoxicity and good biocompatibility, indicating that boron‐functionalization of acenes is a promising strategy toward organic sonosensitizers for SDT.
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- Award ID(s):
- 1954122
- PAR ID:
- 10384630
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Materials
- Volume:
- 34
- Issue:
- 49
- ISSN:
- 0935-9648
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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