Solvent Effects on Emission Spectra

  • Joseph R. Lakowicz

Abstract

Solvent polarity and the local environment have profound effects on the emission spectra of polar fluorophores. These effects are the origin of the Stokes’ shift, which is one of the earliest observations in fluorescence. Emission spectra are easily measured, and as a result, there are numerous publications on emission spectra of fluorophores in different solvents and when bound to proteins, membranes, and nucleic acids. One common use of solvent effects is to determine the polarity of the probe binding site on the macromolecule. This is accomplished by comparison of the emission spectra and/or quantum yields of the fluorophore when it is bound to the macromolecule and when it is dissolved in solvents of different polarity. However, there are many additional instances where solvent effects are used. Suppose a fluorescent ligand binds to a protein. Binding is usually accompanied by a spectral shift due to the different environment for the bound ligand. Alternatively, the ligand may induce a spectral shift in the intrinsic or extrinsic protein fluorescence. Additionally, fluorophores often display spectral shifts when they bind to membranes.

Keywords

Dipole Moment Emission Spectrum Solvent Polarity Solvent Effect Spectral Shift 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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References

  1. 1.
    Safarzadeh-Amiri, A., Thompson, M., and Krull, U. J., 1989, Trans-4-dimethylamino-4-(1-oxobutyl)stilbene: A new fluorescent probe of the bilayer lipid membrane, J. Photochem. Photobiol. A: Chem. 47: 299–308.CrossRefGoogle Scholar
  2. 2.
    Von Lippert, E., 1957, Spektroskopische bistimmung des dipolmomentes aromatischer verbindungen im ersten angeregten singulettzustand, Z. Electrochem. 61: 962–975.Google Scholar
  3. 3.
    Mataga, N., Kaifu, Y., and Koizumi, M., 1956, Solvent effects upon fluorescence spectra and the dipole moments of excited molecules, Bull. Chem. Soc. Jpn. 29: 465–470.CrossRefGoogle Scholar
  4. 4.
    Rettig, W., 1986, Charge separation in excited states of decoupled systems—TICT compounds and implications regarding the development of new laser dyes and the primary processes of vision and photosynthesis, Angew. Chem. Int. Ed. Engl. 25: 971–988.CrossRefGoogle Scholar
  5. 5.
    Bayliss, N. S., 1950, The effect of the electrostatic polarization of the solvent on electronic absorption spectra in solution, J. Chem. Phys. 18: 292–296.CrossRefGoogle Scholar
  6. 6.
    Bayliss, N. S., and McRae, E. G., 1954, Solvent effects in organic spectra: Dipole forces and the Franck–Condon principle, J. Phys. Chem. 58: 1002–1006.CrossRefGoogle Scholar
  7. 7.
    McRae, E. G., 1956, Theory of solvent effects of molecular electronic spectra. Frequency shifts, J. Phys. Chem. 61: 562–572.CrossRefGoogle Scholar
  8. 8.
    Baumann, W., and Bischof, H., 1982, Integral electro optical emission measurements. A new method for the determination of dipole moments of molecules in fluorescent states, J. Mol. Struct. 84: 18 1193.Google Scholar
  9. 9.
    Kawski, A., 1992, Solvent-shift effect of electronic spectra and excited state dipole moments, in Progress in Photochemistry and Photophysics, J. F. Rabek (ed.), CRC Press, New York, pp. 1–47.Google Scholar
  10. 10.
    Seliskar, C. J., and Brand, L., 1971, Electronic spectra of 2-aminonaphthalene-6-sulfonate and related molecules. II, Effects of solvent medium on the absorption and fluorescence spectra, J. Am. Chem. Soc. 93: 5414–5420.CrossRefGoogle Scholar
  11. 11.
    Suppan, P., 1990, Solvatochromic shifts: The influence of the medium on the energy of electronic states, J. Photochem. Photobiol. A: Chem. 50: 293–330.CrossRefGoogle Scholar
  12. 12.
    Bakhshiev, N. G., 1961, Universal molecular interactions and their effect on the position of the electronic spectra of molecules in two component solutions I. Theory (liquid solutions), Opt. Spectrosc. 10: 379–384.Google Scholar
  13. 13.
    Bakhshiev, N. G., 1962, Universal molecular interactions and theireffects on the position of electronic spectra of molecules in two-component solutions. IV. Dependence on the magnitude of the Stokes shift in the solvent luminescence spectrum (liquid solutions), Opt. Spectrosc. 12: 309–313.Google Scholar
  14. 14.
    Bakhshiev, N. G., 1962, Universal intermolecular interactions and their effect on the position of the electronic spectra of molecules in two-component solutions, Opt. Spectrosc. 13: 24–29.Google Scholar
  15. 15.
    Weber, G., and Laurence, D. J. R., 1954, Fluorescent indicators of absorption in aqueous solution and on the solid phase, Biochem. J. 56:xxxi.Google Scholar
  16. 16.
    Slavik, J., 1982, Anilinonaphthalene sulfonate as a probe of membrane composition and function, Biochim. Biophys. Acta 694: 1–25.CrossRefGoogle Scholar
  17. 17.
    McClure, W. O., and Edelman, G. M., 1954, Fluorescent probes for conformational states of proteins. I. Mechanism of fluorescence of 2-p-toluidinylnaphthalene-6-sulfonate, a hydrophobic probe, Biochemistry 5: 1908–1919.CrossRefGoogle Scholar
  18. 18.
    Brand, L., Seliskar, C. J., and Turner, D. C., 1971, The effects of chemical environment on fluorescence probes, in Probes of Structure and Function of Macromolecules and Membranes, B. Chance, C. P. Lee, and J.-K. Blaisie (eds.), Academic Press, New York, pp. 17–39.Google Scholar
  19. 19.
    Turner, D.C., and Brand, L., 1968, Quantitative estimation of protein binding site polarity. Fluorescence of N-arylaminonaphthalenesulfonates, Biochemistry 7: 3381–3390.CrossRefGoogle Scholar
  20. 20.
    Kosower, E. M., and Dodiuk, H., 1978, Intramolecular donor–acceptor systems. 3. A third type of emitting singlet state for N-alkyl6-N-arylamino-2-naphthalenesulfonates. Solvent modulation of substituent effects on charge-transfer emissions, J. Am. Chem. Soc. 100: 4173–4179.CrossRefGoogle Scholar
  21. 21.
    Kosower, E. M., and Kanety, H., 1983, Intramolecular donor–acceptor systems. 10. Multiple fluorescence from 8-(phenylamino)-1naphthalenesulfonates, J. Am. Chem. Soc. 105: 6236–6243.CrossRefGoogle Scholar
  22. 22.
    Kosower, E. M., and Huppert, D., 1986, Excited state electron and proton transfers, Annu. Rev. Phys. Chem. 37: 127–156.CrossRefGoogle Scholar
  23. 23.
    Wilt, J. W., and Chwang, W. K., 1974, Fluorescence of 2-N-arylamino-6-naphthalenesulfonates in glycerol, J. Am. Chem. Soc. 96: 6195–6196.CrossRefGoogle Scholar
  24. 24.
    Huppert, D., Ittah, V., and Kosower, E. M., 1988, New insights into the mechanism of fast intramolecular electron transfer, Chem. Phys. Lett. 144: 15–22.CrossRefGoogle Scholar
  25. 25.
    Kosower, E. M., 1968, An Introduction to Physical Organic Chemistry, John Wiley amp; Sons, New York, pp. 293–382.Google Scholar
  26. 26.
    Kosower, E. M., 1958, The effect of solvent on spectra. I. A new empirical measure of solvent polarity: Z-values, J. Am. Chem. Soc. 80: 3253–3260.CrossRefGoogle Scholar
  27. 27.
    Dimroth, K., Reichardt, C., Siepmann, T., and Bohlmann, F, 1963, Über pyridinium-N-phenol-betaine und ihre verwendung zur charakterisierung der polarität von lösungsmitteln, Liebigs Ann. Chem. 661: 1–37.CrossRefGoogle Scholar
  28. 28.
    Reichardt, C., and Harbusch-Gömert, E., 1983, Erweiterung, korrektur und neudefinition der E -.lösungsmittelpolaritätsskala mit hilfe eines lipophilen penta-tert-butyl-substituierten pyridinium-Nphenolat-betainfarbstoffes, Liebigs Ann. Chem. 5: 721–743.CrossRefGoogle Scholar
  29. 29.
    Kamlet, M. J., Abboud, J. L., and Taft, R. W., 1977, The solvatochromic comparison method. 6. The it scale of solvent polarities, J. Am. Chem. Soc. 99: 6027–6038.CrossRefGoogle Scholar
  30. 30.
    Von Reichardt, C., 1965, Empirische parameter der lösungsmittelpolarität, Angew. Chem. 77: 30–40.CrossRefGoogle Scholar
  31. 31.
    Buncel, E., and Rajagopal, S., 1990, Solvatochromism and solvent polarity scales, Acc. Chem. Res. 23: 226–231.CrossRefGoogle Scholar
  32. 32.
    Reichardt, C., 1994, Solvatochromic dyes as solvent polarity indicators, Chem. Rev. 94: 2319–2358.CrossRefGoogle Scholar
  33. 33.
    Valeur, B., 1993, Fluorescent probes for evaluation of local physical and structural parameters, in Molecular Luminescence Spectroscopy, Methods and Applications, Part 3, S. G. Schulman (ed.), John Wiley amp; Sons, pp. 25–84.Google Scholar
  34. 34.
    Bakhshiev, N. G., 1962, Universal molecular interactions and their effect on the position of electronic spectra of molecules in two-component solutions, Opt. Spectrosc. 12: 261–264.Google Scholar
  35. 35.
    Perov, A. N., 1980, Energy of intermediate pair interactions as a characteristic of their nature. Theory of the solvato (fluoro) chromism of three-component solutions, Opt. Spectmsc. 49: 37 1374.Google Scholar
  36. 36.
    Neporent, B. S., and Bakhshiev, N. G., 1960, On the role of universal and specific intermolecular interactions in the influence of the solvent on the electronic spectra of molecules, Opt. Spectrosc. 8: 408–413.Google Scholar
  37. 37.
    Cherkasov, A. S., 1960, Influence of the solvent on the fluorescence spectra of acetylanthracenes, Akad. Nauk SSSR Bull. Phys. Sci. 24: 597–601.Google Scholar
  38. 38.
    Tamaki, T., 1982, The photoassociation of 1- and 2-acetylanthracene with methanol, Bull. Chem. Soc. Jpn. 55: 1761–1767.CrossRefGoogle Scholar
  39. 39.
    Tamaki, T., 1980, Polar fluorescent state of 1- and 2-acylanthracenes. II. The perturbation of protic solvents, Bull. Chem.Soc. Jpn. 53: 577–582CrossRefGoogle Scholar
  40. 40.
    Fery-Forgues, S., Fayet, J.-P., and Lopez, A., 1993, Drastic changes in the fluorescence properties of NBD probes with the polarity of the medium: Involvement of a TICT state, J. Photochem. Photobiol. A: Chem. 70: 229–243.CrossRefGoogle Scholar
  41. 41.
    Mazères, S., Schram, V., Tocanne, J.-F., and Lopez, A., 1996, 7-Nitrobenz-2-oxa-1,3-diazole-4-yl-labeled phospholipids in lipid membranes: Differences in fluorescence behavior, Biophys. J. 71: 327–335.Google Scholar
  42. 42.
    Perochon, E., and Tocanne, J.-E, 1991, Synthesis and phase properties of phosphatidylcholine labeled with 8-(2-anthroyl)-octanoic acid, a solvatochromic fluorescent probe, Chem. Phys. Lipids 58: 717.CrossRefGoogle Scholar
  43. 43.
    Perochon, E., Lopez, A., and Tocanne, J. F., 1991, Fluorescence properties of methyl 8-(2-anthroyl) octanoate, a solvatochromic lipophilic probe, Chem. Phys. Lipids 59: 17–28.CrossRefGoogle Scholar
  44. 44.
    Rosenberg, H. M., and Eimutus, E., 1966, Solvent shifts in electronic spectra I. Stokes’ shift in a series of homologous aromatic amines, Spectrochim. Acta 22: 1751–1757.CrossRefGoogle Scholar
  45. 45.
    Werner, T. C., and Hercules, D. M., 1969, The fluorescence of 9-anthroic acid and its esters. Environmental effects on excited-state behavior, J. Phys. Chem. 73: 2005–2011.CrossRefGoogle Scholar
  46. 46.
    Werner, T. C., and Hoffman, R. M., 1973, Relation between an excited state geometry change and the solvent dependence of 9-methyl anthroate fluorescence, J. Phys. Chem. 77: 1611–1615.CrossRefGoogle Scholar
  47. 47.
    Werner, T. C., Matthews, T., and Soller, B., 1976, An investigation of the fluorescence properties of carboxyl substituted anthracenes, J. Phys. Chem. 80: 533–541.CrossRefGoogle Scholar
  48. 48.
    Garrison, M. D., Doh, L. M., Potts, R. O., and Abraham, W., 1994, Fluorescence spectroscopy of 9-anthroyloxy fatty acids in solvents, Chem. Phys. Lipids 70: 155–162.CrossRefGoogle Scholar
  49. 49.
    Berberan-Santos, M. N., Prieto, M. J. E., and Szabo, A. G, 1991, Excited-state intramolecular relaxation of the lipophillic probe 12(9-anthroyloxy)stearic acid, J. Phys. Chem. 95: 5471–5475.CrossRefGoogle Scholar
  50. 50.
    Thulbom, K. R., and Sawyer, W. H., 1978, Properties and the locations of a set of fluorescent probes sensitive to the fluidity gradient of the lipid bilayer, Biochim. Biophys. Acta 511: 125–140.CrossRefGoogle Scholar
  51. 51.
    Badea, M. G., De Toma, R. P., and Brand, L., 1978, Nanosecond relaxation processes in liposomes, Biophys. J. 24: 197–212.CrossRefGoogle Scholar
  52. 52.
    Lakowicz, J. R., and Baiter, A., 1982, Direct recording of the initially excited and the solvent relaxed fluorescence emission of a tryptophan derivative in viscous solution by phase sensitive detection of fluorescence, Photochem. Photobiol. 36: 125–132.CrossRefGoogle Scholar
  53. 53.
    Lakowicz, J. R., Bevan, D. R., Maliwal, B. P., Cherek, H., and Baiter, A., 1983, Synthesis and characterization of a fluorescence probe of the phase transition and dynamic properties of membranes, Biochemistry 22: 5714–5722.CrossRefGoogle Scholar
  54. 54.
    Weber, G., and Farris, F. J., 1979, Synthesis and spectral properties of a hydrophobic fluorescent probe: 6-Propionyl-2-(dimethylamino)naphthalene, Biochemistry 18: 3075–3078.CrossRefGoogle Scholar
  55. 55.
    Sire, O., Alpert, B., and Royer, C. A., 1996, Probing pH and pressure effects of the apomyoglobin heme pocket with the 2’-(N,N-dimethylamino)-6-naphthoyl-4-trans-cyclohexanoic acid fluorophore, Biophys. J. 70: 2903–2914.CrossRefGoogle Scholar
  56. 56.
    Prendergast, E. G., Meyer, M., Carlson, G. L., Iida, S., and Potter, J. D., 1983, Synthesis, spectral properties, and use of 6-acryloyl-2-dimethylaminonaphthalene (acrylodan), J. Biol. Chem. 258: 7541–7544.Google Scholar
  57. 57.
    Hendrickson, H. S., Dumdei, E. J., Batchelder, A. G., and Carlson, G. L., 1987, Synthesis of Prodan-phosphatidylcholine, a new fluorescent probe, and its interactions with pancreatic and snake venom phospholipases A2, Biochemistry 26: 3697–3703.CrossRefGoogle Scholar
  58. 58.
    Sandez, M. I., Suarez, A., Rios, M. A., Balo, M. C., Fernandez, E, and Lopez, C., 1996, Spectroscopic study of new fluorescent probes, Photochem. Photobiol. 64: 486–491.CrossRefGoogle Scholar
  59. 59.
    Viard, M., Gallay, J., Vincent, M., Meyer, O., Robert, B., and Paternostre, M., 1997, Laurdan solvatochromism: Solvent dielectric relaxation and intramolecular excited-state reaction, Biophys. J. 73: 2221–2234.CrossRefGoogle Scholar
  60. 60.
    Zurawsky, W. P., and Scarlata, S. E, 1992, Preferential solvation of 6-propionyl(N,N-dimethylamino)naphthalene in binary, polar solvent mixtures, J. Phys. Chem. 96: 6012–6016.CrossRefGoogle Scholar
  61. 61.
    Ilich, P., and Prendergast, F. G., 1989, Singlet adiabatic states of solvated PRODAN: A semiempirical molecular orbital study, J. Phys. Chem. 93: 4441–4447.CrossRefGoogle Scholar
  62. 62.
    Catalan, J., Perez, P., Laynez, J., and Blanco, E G., 1991, Analysis of the solvent effect on the photophysics properties of 6-propionyl2-(dimethylamino)naphthalene (PRODAN), J. Fluoresc. 1(4): 215223.Google Scholar
  63. 63.
    Parusel, A., Schneider, E W., and Köhler, G.,1997, An ab initio study on excited and ground state properties of the organic fluorescence probe PRODAN, J. Mol. Struct. (Theochem) 398–399: 341–346.Google Scholar
  64. 64.
    Nowak, W., Sygula, A., Adamczak, P., and Baiter, A., 1986, On the possibility of fluorescence from twisted intramolecular charge transfer states of 2-dimethylamino-6-acylnaphthalenes. A quantum-chemical study, J. Mol. Struct. 139: 13–23.CrossRefGoogle Scholar
  65. 65.
    Baiter, A., Nowak, W., Pawelkiewicz, W., and Kowalczyk, A., 1988, Some remarks on the interpretation of the spectral properties of Prodan, Chem. Phys. Lett. 143: 565–570.CrossRefGoogle Scholar
  66. 66.
    Rettig, W., and Lapouyade, R., 1994, Fluorescence probes based on twisted intramolecular charge transfer (TICT) states and other adiabatic photoreactions, in Topics in Fluorescence Spectroscopy, Volume 4: Probe Design and Chemical Sensing, J. R. Lakowicz (ed.), Plenum Press, New York, pp. 109–149.Google Scholar
  67. 67.
    Comeli(3en, C., and Rettig, W., 1994, Unusual fluorescence red shifts in TICT-forming boranes, J. Fluoresc. 4 (1): 71–74.Google Scholar
  68. 68.
    Vollmer, E, Rettig, W., and Birckner, E., 1994, Photochemical mechanisms producing large fluorescence Stokes’ shifts, J. Fluorese. 4 (1): 65–69.CrossRefGoogle Scholar
  69. 69.
    Rotkiewicz, K., Grellmann, K. H., and Grabowski, Z. R., 1973, Reinterpretation of the anomalous fluorescence of p-N,N-dimethylamino-benzonitrile, Chem. Phys. Lett. 19: 315–318.CrossRefGoogle Scholar
  70. 70.
    Grabowski, Z. R., Rotkiewicz, K., and Siemiarczuk, A., 1979, Dual fluorescence of donor—acceptor molecules and the twisted intramolecular charge transfer TICT states, J. Lumin. 18: 420–424.CrossRefGoogle Scholar
  71. 71.
    Belletête, M., and Durocher, G., 1989, Conformational changes upon excitation of dimethylamino para-substituted 3H-indoles. Viscosity and solvent effects, J. Phys. Chem. 93: 1793–1799.CrossRefGoogle Scholar
  72. 72.
    Jones, G., Jackson, W. R., Choi, C.-Y., and Bergmark, W. R., 1985, Solvent effects on emission yield and lifetime for coumarin laser dyes. Requirements for a rotatory decay mechanism, J. Phys. Chem. 89: 294–300.CrossRefGoogle Scholar
  73. 73.
    Ayuk, A. A., Rettig, W., and Lippert, E., 1981, Temperature and viscosity effects on an excited state equilibrium as revealed from the dual fluorescence of very dilute solutions of 1-dimethylamino-4-cyanonaphthalene, Ber. Bunsenges. Phys. Chem. 85: 553–555.CrossRefGoogle Scholar
  74. 74.
    Cherkasov, A. S., and Dragneva, G. I., 1961, Influence of solvent viscosity on the fluorescence spectra of certain organic compounds, Opt. Spectrosc. 10: 238–241.Google Scholar
  75. 75.
    Bakhshiev, N. G., and Piterskaya, I. V., 1965, Universal molecular interactions and their effect on the electronic spectra of molecules in two-component solutions X, Opt. Spectrosc. 19: 390–395.Google Scholar
  76. 76.
    Macgregor, R. B., and Weber, G., 1981, Fluorophores in polar media. Spectral effects of the Langevin distribution of electrostatic interactions, Proc. N.Y. Acad. Sci. 366: 140–154.CrossRefGoogle Scholar
  77. 77.
    Piterskaya, I. V., and Bakhshiev, N. G., 1963, Quantitative investigation of the temperature dependence of the absorption and fluorescence spectra of complex molecules, Bull. Acad. Sci. USSR, Phys. Ser. 27: 625–629.Google Scholar
  78. 78.
    Kawski, A., 1997, Thermochromic shifts of electronic spectra and excited state dipole moments, Asian J. Spectrosc. 1: 27–38.Google Scholar
  79. 79.
    Lakowicz, J. R., Cherek, H., Lazcko, G., and Gratton, E., 1984, Time-resolved fluorescence emission spectra of labeled phospholipid vesicles. As observed using multi-frequency phase-modulation fluorometry, Biochim. Biophys. Acta 777: 183–193.CrossRefGoogle Scholar
  80. 80.
    Marriott, G., Zechel, K., and Jovin, T. M., 1988, Spectroscopic and functional characterization of an environmentally sensitive fluorescent actin conjugate, Biochemistry 27: 6214–6220.CrossRefGoogle Scholar
  81. 81.
    Richieri, G. V, Ogata, R. T., and Kleinfeld, A. M., 1992, A fluorescently labeled intestinal fatty acid binding protein, J. Biol. Chem. 267: 23495–23501.Google Scholar
  82. 82.
    Richieri, G. V., And, A., and Kleinfeld, A. M., 1993, Interactions of long-chain fatty acids and albumin: Determination of free fatty acid levels using the fluorescent probe ADIFAB, Biochemistry 32: 75747580.Google Scholar
  83. 83.
    Richieri, G. V., Ogata, R. T., and Kleinfeld, A. M., 1996, Kinetics of fatty acid interactions with fatty acid binding proteins from adipocyte, heart, and intestine, J. Biol. Chem. 271: 11291–11300.CrossRefGoogle Scholar
  84. 84.
    Richieri, G. V., Ogata, R. T., and Kleinfeld, A. M., 1996, Thermodynamic and kinetic properties of fatty acid interactions with rat liver fatty acid-binding protein, J. Biol. Chem. 271: 31068–31074.CrossRefGoogle Scholar
  85. 85.
    Richieri, G. V, Ogata, R. T., and Kleinfeld, A. M., 1994, Equilibrium constants for the binding of fatty acids with fatty acid-binding proteins from adipocyte, intestine, heart and liver measured with the fluorescent probe ADIFAB, J. Biol. Chem. 269: 23918–23930.Google Scholar
  86. 86.
    Richieri, G. V, and Kleinfeld, A. M., 1995, Unbound free fatty acid levels in human serum, J. Lipid Res. 36: 229–240.Google Scholar
  87. 87.
    Kleinfeld, A. M., Prothro, D., Brown, D. L., Davis, R. C., Richieri, G. V, and DeMaria, A., 1996, Increases in serum unbound free fatty acid levels following coronary angioplasty, Am. J. Cardiol. 78: 1350–1354.CrossRefGoogle Scholar
  88. 88.
    LaPorte, D. C., Wierman, B. M., and Storm, D. R., 1980, Calcium-induced exposure of a hydrophobic surface on calmodulin, Biochemistry 19: 3814–3819.CrossRefGoogle Scholar
  89. 89.
    Wang, Y., Ikeda, T., Ikeda, H., Ueno, A., and Toda, E, 1994, Dansyl-(3-cyclodextrins as fluorescent sensors responsive to organic compounds, Bull. Chem. Soc. Jpn. 67: 1598–1607.CrossRefGoogle Scholar
  90. 90.
    Nagata, K., Furuike, T., and Nishimura, S.-I., 1995, Fluorescence-labeled synthetic glycopolymers: A new type of sugar ligands of lectins, J. Biochem. (Tokyo) 118: 278–284.Google Scholar
  91. 91.
    Perochon, E., Lopez, A., and Tocanne, J. E, 1992, Polarity of lipid bilayers. A fluorescence investigation, Biochemistry 31: 7672–7682.CrossRefGoogle Scholar
  92. 92.
    BioProbes 25, New Products and Applications, Molecular Probes, Inc., Eugene, Oregon, May 1997.Google Scholar
  93. 93.
    Diwu, Z., Lu, Y, Zhang, C., Kalubert, D. H., and Haugland, R. P., 1997, Fluorescent molecular probes II. The synthesis, spectral properties and use of fluorescent solvatochromic DapoxylTlGt dyes, Photochem. Photobiol. 66: 424–431.CrossRefGoogle Scholar
  94. 94.
    Gryczynski, I., Wiczk, W., Lakowicz, J. R., and Johnson, M. L., 1989, Decay time distribution analysis of Yt-base in benzene-methanol mixtures, J. Photochem. Photobiol. B: Biol. 4: 159–170.CrossRefGoogle Scholar
  95. 95.
    Gryczynski, I., Wiczk, W., Johnson, M. L., and Lakowicz, J. R., 1988, Lifetime distributions and anisotropy decays of indole fluorescence in cyclohexane/ethanol mixtures by frequency-domain fluorometry, Biophys. Chem. 32: 173–185.CrossRefGoogle Scholar
  96. 96.
    Gryczynski, I., unpublished observations.Google Scholar

Copyright information

© Springer Science+Business Media New York 1999

Authors and Affiliations

  • Joseph R. Lakowicz
    • 1
  1. 1.University of Maryland School of MedicineBaltimoreUSA

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