Quantitative comparison of excited state properties and intensity- dependent photosensitization by rose bengal.

A quantitative (multistep) excitation-deactivation model of rose bengal (RB) has been developed which includes energy and electron transfer to oxygen and the possibility of photoproduct formation via higher excited triplet-singlet states. The model is based on previous measurements of non-linear absorption (NLA) and emission of RB with picosecond pulses at 532 nm and on NLA measurements with nanosecond pulses. A coupled rate equation and photon transport equation approach for non-linear light-matter interaction is used. The resulting term scheme with all relevant excited state parameters confirms that (i) in the first excited state of RB, relevant absorption at 532 nm takes place only in the triplet, and (ii) the previously reported intensity dependence of RB-sensitized enzyme inhibition is well modelled by the intensity-dependent RB-T1 population and (as the main process) subsequent energy transfer to form singlet oxygen.

[1]  H. Stiel,et al.  Flexible instrument for time‐correlated single‐photon counting , 1991 .

[2]  W. Mcgimpsey,et al.  Photochemistry of the triplet T2 state of anthracene , 1993 .

[3]  D. Nikogosyan.  Definition of Photoreaction Quantum Yield at Two-quantum Excitation of Molecules in Solution , 1987 .

[4]  I. Kochevar,et al.  Laser intensity and wavelength dependence of Rose-Bengal-photosensitized inhibition of red blood cell acetylcholinesterase. , 1989, Biochimica et biophysica acta.

[5]  H. Stiel,et al.  Excited-state properties of 20-chloro-chlorophyll a , 1990 .

[6]  T. Sarna,et al.  Rose bengal radicals and their reactivity , 1990 .

[7]  J. Scaiano,et al.  Photochemistry of organic reaction intermediates: novel reaction paths induced by two-photon laser excitation , 1988 .

[8]  J. Yardley,et al.  Nonlinear optical properties of organic dye dimer-monomer systems , 1988 .

[9]  J. M. Morris,et al.  Picosecond Fluorescence Studies of Xanthene Dyes , 1977 .

[10]  M. Rodgers,et al.  Lifetime of oxygen (O2(1.DELTA.g)) in liquid water as determined by time-resolved infrared luminescence measurements , 1982 .

[11]  R. Wilson,et al.  High intensity laser photochemistry of organic molecules in solution , 1993 .

[12]  E. Oliveros,et al.  Determination of the Quantum Yield of Intersystem Crossing of Rose Bengal , 1987 .

[13]  W. Mcgimpsey,et al.  AN EFFICIENT OXYGEN INDEPENDENT TWO‐PHOTON PHOTOSENSITIZATION MECHANISM , 1994, Photochemistry and photobiology.

[14]  I. Kochevar,et al.  A wavelength dependent mechanism for rose bengal-sensitized photoinhibition of red cell acetylcholinesterase. , 1991, Biochimica et biophysica acta.

[15]  M. Rodgers,et al.  LASER FLASH PHOTOKINETIC STUDIES OF ROSE BENGAL SENSITIZED PHOTODYNAMIC INTERACTIONS OF NUCLEOTIDES AND DNA , 1987, Photochemistry and photobiology.

[16]  G. Buettner,et al.  THE STEPWISE BIPHOTONIC PHOTOIONIZATION OF CHLORPROMAZINE AS SEEN BY LASER FLASH PHOTOLYSIS , 1989, Photochemistry and photobiology.

[17]  E. V. Khoroshilova,et al.  Photochemistry of uridine on high intensity laser UV irradiation. , 1990, Journal of photochemistry and photobiology. B, Biology.

[18]  S. R. Kennedy,et al.  Determination of the Lifetime of the Second Excited Triplet State of Anthracenes , 1991 .

[19]  H. Stiel,et al.  Two-photon excitation of alkyl-substituted magnesium phthalocyanine: radical formation via higher excited states , 1994 .

[20]  T. Gantchev,et al.  Photoproducts generated from hematoporphyrin under high-intensity picosecond flash photolysis , 1990, Radiation and environmental biophysics.

[21]  A. Shafferman,et al.  Intensity dependence in laser flash photolysis experiments: Hydrated electron formation from ferrocyanide, tyrosine, and tryptophan , 1976 .