Photodynamic Therapy Mediated by Fullerenes and their Derivatives
7 Conclusion & executive summary
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- Ris (Zotero)
- Reference Manager
The research activity on buckminsterfullerene (C60) and other soluble functionalized fullerenes in the last few decades has been extraordinary. A host of physical and chemical properties of these materials have now been established, and their potential applications in several areas are now apparent. In biomedical applications, functionalized fullerenes have been studied in different in vitro and in vivo studies and have shown promising effects as anti-cancer and antimicrobial (bacteria, fungus and virus) nanomedicines. Fullerenes have been widely studied in recent years as potential PS that could mediate PDT of diverse diseases. Most of these reports have been confined to in vitro studies where viruses, bacteria, fungi or cancer cells have been incubated with a diverse array of functionalized or solubilized fullerene compounds followed by illumination with light that is usually UVA, blue, green or white because the absorption spectrum of fullerenes is biased towards lower wavelengths. Since in vivo PDT usually uses red light for its improved tissue-penetrating properties, it was unclear whether fullerenes would mediate effective PDT in vivo. This question can now be answered in the affirmative. In fact, the report in which mice suffered toxicity after fullerene PDT with red light but exhibited a beneficial therapeutic effect after white light illumination suggests that this supposed drawback might actually be an advantage instead. Future studies will include synthesis of new fullerene derivatives particularly those with light-harvesting antennae to broaden the range of activating light that can be used, hence increasing light penetration depth into tissue. More experiments should be designed to increase understanding of the mechanisms that govern the balance between type I and type II reactive oxygen species. These studies will establish whether fullerenes can compete with more traditional PS in clinical applications of PDT.