Final Report Summary - PHOTOCHROMES (Photochromic Systems for Solid State Molecular Electronic Devices and Light-Activated Cancer Drugs.)
Within the frames of the PHOTOCHROME research programme, photochromic molecules have been used in the contexts of light-activated cancer drugs (by controlling the DNA-binding properties) and molecular logic devices. We have proven that photochromic molecules can indeed be used for both the abovementioned purposes. More specifically, we have shown the following:
•Spiropyran photoswitches can be reversibly isomerized between a form that binds to DNA (MC) and a form that display no detectable DNA-binding (SP).
•Other spiropyran derivatives only binds to DNA after being isomerized to the MC form at pH 6, whereas no binding is seen at pH 7. This is highly relevant, as the pH of cancer cells are typically more acidic compared to normal cells.
•The SP form displays no cytotoxic effect on live cells. Isomerization of SP to MC inside the cells induces a cytotoxic response. Hence, photoactivated cytotoxicity of a photochromic molecule is clearly proven.
•Several spin-off projects have been initiated, all relying on the ability to photochromically control DNA-binding. DNA chirality transfer and the reversible control of energy transfer on DNA scaffolds deserve special mentioning.
•The function of several advanced logic operations have been mimicked on the molecular scale using photochromic supramolecules. Most important, a photochromic triad was designed that can perform the function of 15 different logic functions. This is by far the most sophisticated molecular logic platform ever reported.
•Spiropyran photoswitches can be reversibly isomerized between a form that binds to DNA (MC) and a form that display no detectable DNA-binding (SP).
•Other spiropyran derivatives only binds to DNA after being isomerized to the MC form at pH 6, whereas no binding is seen at pH 7. This is highly relevant, as the pH of cancer cells are typically more acidic compared to normal cells.
•The SP form displays no cytotoxic effect on live cells. Isomerization of SP to MC inside the cells induces a cytotoxic response. Hence, photoactivated cytotoxicity of a photochromic molecule is clearly proven.
•Several spin-off projects have been initiated, all relying on the ability to photochromically control DNA-binding. DNA chirality transfer and the reversible control of energy transfer on DNA scaffolds deserve special mentioning.
•The function of several advanced logic operations have been mimicked on the molecular scale using photochromic supramolecules. Most important, a photochromic triad was designed that can perform the function of 15 different logic functions. This is by far the most sophisticated molecular logic platform ever reported.