RT Journal Article
T1 Ultrafast deactivation of bilirubin: dark intermediates and two-photon isomerization
A1 Carreira Blanco, Carlos
A1 Singer, Patrick
A1 Diller, Rolf
A1 Pérez Lustres, José Luis
AB Bilirubin is a neurotoxic product responsible for neonatal jaundice, which is generally treated by phototherapy. The photoreaction involves ultrafast internal conversion via an elusive intermediate and Z–E isomerization with minor yield (less than 3% in solution). The structure of the intermediate remains unclear. Here, the combination of UV-vis and mid-IR ultrafast transient absorption spectroscopy reports a comprehensive picture of the mechanism and provides essential structural information about the intermediate species. Thus, spectral dynamics during the earliest ps unveils a wavepacket travelling from the Franck–Condon region to the crossing point with a dark state. The latter shows a tighter molecular skeleton than the ground state and decays with 15 ps time constant. Remarkably, the relative contribution of a non-decaying component increases linearly with pump energy, suggesting that Z–E isomerization could also be triggered by two-photon excitation. Implications for the photochemistry of protein-bound open tetrapyrroles are discussed
PB Royal Society of Chemistry
SN 1463-9076
YR 2016
FD 2016
LK http://hdl.handle.net/10347/17070
UL http://hdl.handle.net/10347/17070
LA eng
NO Carreira-Blanco, C., Singer, P., Diller, R., & Luis Pérez Lustres, J. (2016). Ultrafast deactivation of bilirubin: dark intermediates and two-photon isomerization. Physical Chemistry Chemical Physics, 18(10), 7148-7155. doi: 10.1039/c5cp06971h
NO JLPL thanks the Spanish Ministry of Science and Innovation (MICINN) for funding through the grant CTQ2010-17026 (FEDER Funds) and the ‘‘Ramón y Cajal’’ Program 2009, aswell as the Xunta de Galicia (Spain) for grants EM2012/091, GPC2013/052 and R2014/051. CCB thanks the Spanish Ministry of Education for a FPU doctoral grant
DS Minerva
RD 29 abr 2026