PMID- 26282289
OWN - NLM
STAT- PubMed-not-MEDLINE
DCOM- 20150819
LR  - 20150818
IS  - 1948-7185 (Print)
IS  - 1948-7185 (Linking)
VI  - 4
IP  - 9
DP  - 2013 May 2
TI  - Excited-State Proton-Transfer Processes of DHICA Resolved: From Sub-Picoseconds 
      to Nanoseconds.
PG  - 1383-8
LID - 10.1021/jz400437q [doi]
AB  - Excited-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).
FAU - Corani, Alice
AU  - Corani A
AD  - daggerDepartment of Chemical Physics, Lund University, Box 124, 22100 Lund, Sweden.
FAU - Pezzella, Alessandro
AU  - Pezzella A
AD  - double daggerDepartment of Chemical Sciences, University of Naples, Federico II Via Cintia, 
      80126 Naples, Italy.
FAU - Pascher, Torbjorn
AU  - Pascher T
AD  - daggerDepartment of Chemical Physics, Lund University, Box 124, 22100 Lund, Sweden.
FAU - Gustavsson, Thomas
AU  - Gustavsson T
AD  -  section signLaboratoire Francis Perrin, CEA/DSM/IRAMIS/SPAM-CNRS, URA 2453, CEA/Saclay, 
      F-91191 Gif-sur-Yvette, France.
FAU - Markovitsi, Dimitra
AU  - Markovitsi D
AD  -  section signLaboratoire Francis Perrin, CEA/DSM/IRAMIS/SPAM-CNRS, URA 2453, CEA/Saclay, 
      F-91191 Gif-sur-Yvette, France.
FAU - Huijser, Annemarie
AU  - Huijser A
AD  - daggerDepartment of Chemical Physics, Lund University, Box 124, 22100 Lund, Sweden.
FAU - d'Ischia, Marco
AU  - d'Ischia M
AD  - double daggerDepartment of Chemical Sciences, University of Naples, Federico II Via Cintia, 
      80126 Naples, Italy.
FAU - Sundstrom, Villy
AU  - Sundstrom V
AD  - daggerDepartment of Chemical Physics, Lund University, Box 124, 22100 Lund, Sweden.
LA  - eng
PT  - Journal Article
DEP - 20130410
PL  - United States
TA  - J Phys Chem Lett
JT  - The journal of physical chemistry letters
JID - 101526034
OTO - NOTNLM
OT  - DHICA
OT  - ESPT
OT  - eumelanin
OT  - solvent
OT  - time-resolved fluorescence
EDAT- 2013/05/02 00:00
MHDA- 2013/05/02 00:01
CRDT- 2015/08/19 06:00
PHST- 2015/08/19 06:00 [entrez]
PHST- 2013/05/02 00:00 [pubmed]
PHST- 2013/05/02 00:01 [medline]
AID - 10.1021/jz400437q [doi]
PST - ppublish
SO  - J Phys Chem Lett. 2013 May 2;4(9):1383-8. doi: 10.1021/jz400437q. Epub 2013 Apr 
      10.