Bioorthogonal Turn-On BODIPY-Peptide Photosensitizers for Tailored Photodynamic Therapy

Chemistry. 2020 Aug 6;26(44):10014-10023. doi: 10.1002/chem.202001718. Epub 2020 Jul 23.

Abstract

Photodynamic therapy (PDT) leads to cancer remission via the production of cytotoxic species under photosensitizer (PS) irradiation. However, concomitant damage and dark toxicity can both hinder its use. With this in mind, we have implemented a versatile peptide-based platform of bioorthogonally activatable BODIPY-tetrazine PSs. Confocal microscopy and phototoxicity studies demonstrated that the incorporation of the PS, as a bifunctional module, into a peptide enabled spatial and conditional control of singlet oxygen (1 O2 ) generation. Comparing subcellular distribution, PS confined in the cytoplasmic membrane achieved the highest toxicities (IC50 =0.096±0.003 μm) after activation and without apparent dark toxicity. Our tunable approach will inspire novel probes towards smart PDT.

Keywords: BODIPY; bioorthogonal reactions; peptides; photodynamic therapy; tetrazine.

MeSH terms

  • Boron Compounds / chemistry*
  • Boron Compounds / toxicity
  • HeLa Cells
  • Humans
  • Peptides / chemistry*
  • Photochemotherapy* / methods
  • Photosensitizing Agents / chemistry*
  • Photosensitizing Agents / toxicity

Substances

  • 4,4-difluoro-4-bora-3a,4a-diaza-s-indacene
  • Boron Compounds
  • Peptides
  • Photosensitizing Agents