International audienceExcited-state proton transfer has been hypothesized as a mechanism for UV energy dissipation in eumelanin skin pigments. By using time resolved fluorescence spectroscopy, we show that the previously proposed, but unresolved, excited-state intramolecular proton transfer (ESIPT) of the eumelanin building block 5,6-dihydroxyindole-2-carboxylic acid (DHICA) occurs with a time constant of 300 fs in aqueous solution but completely stops in methanol. The previously disputed excited-state proton transfer involving the 5- or 6-OH groups of the DHICA anion is now found to occur from the 6-OH group to aqueous solvent with a rate constant of 4.0 x 10(8) s(-1)
The UV-dissipative mechanisms of the eumelanin building block 5,6-dihydroxyindole-2-carboxylic acid ...
Ultrafast time-resolved fluorescence spectroscopy has been used to investigate the excited state d...
Ultrafast time-resolved fluorescence spectroscopy has been used to investigate the excited-state dyn...
International audienceExcited-state proton transfer has been hypothesized as a mechanism for UV ener...
Excited-state proton transfer has been hypothesized as a mechanism for UV energy dissipation in eume...
Skin photoprotection is commonly believed to rely on the photochemistry of 5,6-dihydroxyindole (DHI)...
The UV-dissipative mechanisms of the eumelanin building block 5,6-dihydroxyindole-2-carboxylic acid ...
Ultrafast time-resolved fluorescence spectroscopy has been used to investigate the excited-state dyn...
Skin photoprotection is commonly believed to rely on the photochemistry of 5,6-dihydroxyindole (DHI)...
The UV-dissipative mechanisms of the eumelanin building block 5,6-dihydroxyindole-2-carboxylic acid ...
Ultrafast time-resolved fluorescence spectroscopy has been used to investigate the excited state d...
Ultrafast time-resolved fluorescence spectroscopy has been used to investigate the excited-state dyn...
International audienceExcited-state proton transfer has been hypothesized as a mechanism for UV ener...
Excited-state proton transfer has been hypothesized as a mechanism for UV energy dissipation in eume...
Skin photoprotection is commonly believed to rely on the photochemistry of 5,6-dihydroxyindole (DHI)...
The UV-dissipative mechanisms of the eumelanin building block 5,6-dihydroxyindole-2-carboxylic acid ...
Ultrafast time-resolved fluorescence spectroscopy has been used to investigate the excited-state dyn...
Skin photoprotection is commonly believed to rely on the photochemistry of 5,6-dihydroxyindole (DHI)...
The UV-dissipative mechanisms of the eumelanin building block 5,6-dihydroxyindole-2-carboxylic acid ...
Ultrafast time-resolved fluorescence spectroscopy has been used to investigate the excited state d...
Ultrafast time-resolved fluorescence spectroscopy has been used to investigate the excited-state dyn...