Photodynamic therapy and two-photon bio-imaging applications of hydrophobic chromophores through amphiphilic polymer delivery

• DOI: 10.1039/c0pp00381f
• Publication Date: 2011-04-18T10:30:28Z
• Authors: Thibault Gallavardin; Mathieu Maurin; Sophie Marotte; Timea Simon; Ana-Maria Gabudean; Yann Bretonnière; Mikael Lindgren; Frédéric Lerouge; Patrick L. Baldeck; Olivier Stéphan; Yann Leverrier; Jacqueline Marvel; Stéphane Parola; Olivier Maury; Chantal Andraud
• Keywords: Chromophore; Two-photon excitation microscopy; Quantum yield; Biological Imaging

The synthesis and photophysical properties of two lipophilic quadrupolar chromophores featuring anthracenyl (1) or dibromobenzene (2) were described. These two chromophores combined significant two-photon absorption cross-sections with high fluorescence quantum yield for 1 and improved singlet oxygen generation efficiency for 2, in organic solvents. The use of Pluronic nanoparticles allowed a simple and straightforward introduction of these lipophilic chromophores into biological cell media. Their internal distribution in various cell lines was studied using fluorescence microscopy and flow-cytometry following a successful staining that was achieved upon 2 h of incubation. Finally, multiphoton excitation microscopy and photodynamic therapy capability of the chromophores were demonstrated by cell exposure to a 820 nm fs laser and cell death upon one photon resonant irradiation at 436 ± 10 nm, respectively.