Photosensitive Materials
–Fullerenes as Photosensitive Biomaterials–
[Funding sources] SNF, ETH Grant, University of Pennsylvania The Center of Excellence Environmental Toxicology (NIH)
1. Water-soluble fullerene materials
To tackle the extreme insolubility of fullerenes (C60, C70 etc.), which also causing the problem in the usage of them as biomaterials, water-soluble materials were prepared in combination with biocompatible non-toxic polymers, poly(vinylpyrrolidone) (PVP) and PEG. Non-covalent and covalent functionalizations were used to produce both non-defined and well-defined molecular weights and structure. Current studies include addition of targeting moieties to the diseases in vivo and as a photosensitizer in photodynamic therapies.
Publications: J. Chem. Soc., Chem. Commun. 1994, Chem. Commun. 2006, Chem. Commun. 2013, Org. Lett. 2013, Polymer Chem. 2015.
2. Reactive oxygen species and photodynamic therapy (PDT)
In addition to the singlet oxygen (1O2), we discovered the generation of superoxide radical anion (O2•–) from the photoexcited C60 and C70. The DNA cleavage and antibacterial activity was related to this ROS generation. Currently, we are investigating the specific conditions that generate 1O2 and O2•– through, respectively, energy and electron transfer reactions, for the suitable design of photodynamic therapeutic compounds.
Publications: J. Org. Chem. 1996, J. Am. Chem. Soc. 1998, J. Am. Chem. Soc. 2003, Faraday Discuss. 2014, Org. Lett. 2016.
