Abstract
It is reported (J. B. S. Shear and C. Xu and W W. Webb, Photochem. Photobiol.. 1997, 65, 931) that multiphoton near infrared excitation of 5-hydroxytryptophan results in a transient product with green fluorescence. Visible fluorescence from multiphoton excitation enables detection of 5-hydroxytryptophan with extremely high sensitivity and also has potential applications in imaging of biological systems and investigation of protein dynamics. The characteristic fluorescence at 500 nm has now also been observed in a two laser experiment whereby 308 nm photolysis of the solution is followed by an excitation step at 430 nm. Fluorescence was observed in aerated and deaerated solutions and in the presence of ascorbate. Enhancement of fluorescence was observed on addition of ethanol. Transient absorption experiments with 308 nm photolysis showed the formation of three transient species. In the presence of ascorbate the radical formed by photoionisation was quenched, revealing a long-lived species (τ > 1 ms) with a similar absorption spectrum, which is ascribed to the fluorescing species. Fluorescence induced by multiphoton excitation had a lifetime of 910 ± 10 ps and was also unaffected by ascorbate. In the presence of organic solvents there was an increase in fluorescence lifetime, but a decrease in overall fluorescence intensity. The fluorescence intensity and fluorescence lifetime both decreased in acidic solution (pH < 3). The results indicate that the fluorescence does not originate from the 5-indoxyl radical as previously suggested but from one or more other transient products which require further characterisation.
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C. Xu and W. Zipfel and J. B. Shear and R. M. Williams and W. W. Webb, Multiphoton fluorescence excitation: new spectral windows for biological nonlinear microscopy, Proc. Natl. Acad, Sci. USA, 1996, 93, 10763–10768.
B. R. Masters and P. T. C. So and K. H. Kim and C. Beuhler and E. Gratton, Multiphoton excitation microscopy, confocal microscopy, and spectroscopy of living cells and tissues, Adv. Enzymol., 1999, 307, 513–536.
D. J. S. Birch, Multiphoton excited fluorescence spectroscopy of biomolecular systems, Spectrochim. Acta A, 2001, 57, 23f3–2336.
J. B. S. Shear and C. Xu and W. W. Webb, Multiphoton-excited visible emission by serotonin solutions, Photochem. Photobiol., 1997, 65, 93f–936.
M. L. Gostkowski and J. Wei and J. B. Shear, Measurements of serotonin and related indoles using capillary electrophoresis with multiphoton-inducedhyperluminescence, Anal. Biochem., 1998, 260, 244–250
M. L. Gostkowski and J. B. McDoniel and J. Wei and T. E. Curey and J. B. Shear, Characterizing spectrally diverse biological chromophore using capillary electrophoresis with multiphoton-excited fluorescence, J. Am. Chem. Soc., 1998, 120, 18–22.
S. W. Botchway and A. W. Parker and I. Barba and K. Brindle, Development of a time-correlated single photon counting multiphoton laser scanning confocal microscope, Central Laser Facility Annual Report, 2000-2001, RAL-TR-2001-030:pp. 170-171 (http://www.clf.rl.ac.uk/Report/2000-2001/pdf/77.pdfReport/2000-2001/pdf/77.pdf).
M. L. Gostkowski and T. E. Curey and E. Okerberg and T. J. Kang and D. A. V. Bout and J. B. Shear, Effects of molecular oxygen on multiphoton-excited photochemical analysis of hydroxyindoles, Anal. Chem., 2000, 72, 3821–3825.
S. Udenfriend and D. F. Bogdanski and H. Weissbach, Fluorescence characteristics of 5-hydroxytryptamine (serotonin), Science, 1955, 122, 972–973.
S. V. Jovanovic and S. Steenken and M. G. Simic, One-electron reduction potentials of 5-indoxyl radicals, J. Phys. Chem., 1990, 94, 3583–3588.
S. V. Jovanovic and M. G. Simic, Tryptophan metabolites as antioxidants, Life Chem. Rep., 1985, 3, 124–130.
S. Steenken and P. Neta, One-electron reduction potentials of phenols, hydroxy- and aminophenols and related compounds of biological interest, J. Phys. Chem., 1982, 86, 3661–3667.
S. V. Jovanovic and S. Steenken and M. G. Simic, Kinetics and energetics of one-electron transfer reactions involving tryptophan neutral and cation radicals, J. Phys. Chem., 1991, 95, 684–687.
A. T. Al-Kawini and P. O’Neill, G. E. Admas and R. B. Cundall and A. Junino and J. Maignan, Characterisation of the intermediates produced on one-electron oxidation of 4-, 5-, 6-, and 7-hydroxyindoles by the azide radical, J. Chem. Soc, Perkin Trans. 2, 1992, 657–661.
R. H. Bisby and A. W. Parker, Reactions of triplet duroquinone with α-tocopherol and ascorbate: a nanosecond laser flash photolysis and time-resolved resonance Raman investigation, J. Am. Chem. Soc., 1995, 117, 5664–5670.
G. L. Hug, Optical Spectra of nonmetallic inorganic transient species in aqueous solution, National Bureau of Standards, NSRDS-NBS 69, 1981.
G E. Walrafen, Raman spectral studies of water structure, J. Chem. Phys, 1964, 40, 3249–3256.
R. H. Schüler, Oxidation of ascorbate anion by electron transfer to phenoxyl radicals, Radial Res., 1977, 69, 417–433.
M. C. Depew and M. T. Craw and K. MacCormick and J. K. S. Wan, A CIDEP and fluorescence study of the oxidation of vitamin E: the vitamin E radical cation, J.Photochem. Photobiol., B: Biology, 1987, 1, 229–239.
N. Ichinose and S. Tojo and T. Majima, Fluorescence measurement of 3,5-dimethoxyphenol radical cation generated by pulse radiolysis in 1,2-dichloromethane, Chem. Lett., 2000, 1126–1127.
M. J. Gordon and E. Okerberg and M. L. Gostkowski and J. B. Shear, Electrophoretic characterization of transient photochemical reaction products, J. Am. Chem. Soc., 2001, 123, 10780–10781.
D. A. Armstrong and P. S. Surdar, Reduction potentials and exchange-reactions of thiyl radicals and disulfide radical anions, J. Phys. Chem., 1987, 91, 6532–6537.
R. H. Bisby and N. Tabassum, Properties of the radicals formed by one-electron oxidation of acetaminophen, Biochem. Pharmacol., 1988, 37, 2731–2738.
R. M. Williams and J. B. Shear, W. R. Zipfel and S. Maiti and W. W. Webb, Mucosal mast cell secretion processes imaged using three-photon microscopy of 5-hydroxytryptamine autofluorescence, Biophys J., 1999, 76, 1835–1846.
S. Maiti and J. B. Shear and R. M. Williams, W R. Zipfel and W W Webb, Measuring serotonin distribution in live cells with three-photon excitation, Science, 1997, 275, 530–532.
A. Brunmark and E. Cadenas, Redox and addition chemistry of quinoid compounds and its biological significance, Free Rad Biol. Med., 1989, 7, 435–477.
V. A. Hovhannisyan and L. A. Avanessian, Fluorescence study of DNA-dye complexes using one-photon and two-photon picosecond excitation, J. Fluorescence, 1998, 8, 179–183.
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Bisby, R.H., Arvanitidis, M., Botchway, S.W. et al. Investigation of multiphoton-induced fluorescence from solutions of 5-hydroxytryptophan. Photochem Photobiol Sci 2, 157–162 (2003). https://doi.org/10.1039/b206848f
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DOI: https://doi.org/10.1039/b206848f