Photodynamic therapy with hyperbranched poly(ether-ester) chlorin(e6) nanoparticles on human tongue carcinoma CAL-27 cells

Photodiagnosis Photodyn Ther. 2012 Mar;9(1):76-82. doi: 10.1016/j.pdpdt.2011.08.001. Epub 2011 Oct 4.

Abstract

Background: Hyperbranched polymers represent a new class of drug-delivery vehicle that can be used to prepare nanoparticles with uniform size distribution.

Methods: In this study we prepared covalent conjugates between the photosensitizer chlorin(e6) and hyperbranched poly(ether-ester), HPEE. HPEE-ce6 nanoparticles were synthesized by carbodiimide-mediated reaction between HPEE and ce6, and characterized by ultraviolet-visible absorption spectroscopy (UV-Vis), and transmission electron microscopy (TEM). The uptake and phototoxicity of HPEE-ce6 nanoparticles towards human oral tongue cancer CAL-27 cells was detected by confocal laser scanning microscopy (CLSM) and MTT assay, respectively.

Results: The absorption peak of HPEE-ce6 nanoparticles was red-shifted 12-nm compared with ce6, and TEM showed uniform nanoparticles with a diameter of 50-nm. HPEE-ce6 nanoparticles were taken up by CAL-27 cells after 4h incubation and localized in the cytoplasm. The MTT assay showed a significantly (P<0.05) higher phototoxicity compared to free ce6 after 12 J/cm² of 660-nm laser illumination.

Conclusions: This is the first time to our knowledge that hyperbranched polymers have been used in PDT drug delivery.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Cell Line, Tumor
  • Cell Survival
  • Chlorophyllides
  • Humans
  • Microscopy, Confocal
  • Microscopy, Electron, Transmission
  • Nanoparticles / therapeutic use*
  • Photochemotherapy / methods*
  • Photosensitizing Agents / pharmacology*
  • Photosensitizing Agents / therapeutic use
  • Porphyrins / pharmacology*
  • Porphyrins / therapeutic use
  • Tongue Neoplasms / drug therapy*

Substances

  • Chlorophyllides
  • Photosensitizing Agents
  • Porphyrins
  • phytochlorin