Abstract
Naphthalene excited dimer (excimer) fluorescence is observed in the presence of β- and γ-cyclodextrin (CD) at elevated naphthalene (NAP) concentrations (100 μM) but not at low NAP concentrations (5 μM). This is attributed to formation of 2:2 CD:NAP complexes in the former situation. Complexes of NAP with hydroxypropyl β-CD are exclusively 1:1 and no excimer emission is observed. Complexes of NAP with α-CD do not show excimer emission either but the complex stoichiometry is 2:1 CD:NAP in this case. The formation constants for both the 1:1 and 2:2 β-CD:NAP complexes have been determined and they have been found to depend on the ionic strength of the salting out agent NaCl. K1:1 = 377 ± 35 M-1 in the absence of salt and 657 ± 60 M-1 at 1 M NaCl. The corresponding values for K2:2 are (1.0 ± 0.2) × 104 and (4.0 ± 0.5) × 104 M-1, respectively. Stern-Volmer fluorescence quenching studies of the 1:1 and 2:2 species by water-based quenchers (NaI and CsBr) show that both types of complexes protect the fluorophore from the quencher. However, the more completely encapsulated NAP in the 2:2 complex is protected to a greater extent. This is also the case for the 2:2 γ-CD:NAP complex. This protective effect is reflected in the observed rate constants for NAP quenching. For example, kQ = 7.1 × 109 M-1 s-1 for NaI in the absence of CD. This is reduced to 2.1 × 109 M-1 s-1 for the 1:1 complex and 1.2 × 109 M-1 s-1 for the 2:2 complex when 10 mM β-CD is present. A similar pattern is observed for CsBr as quencher. The 2:2 complexes are disrupted in the presence of additives such as linear alcohols and surfactants. The implications of these results for application of CDs for drug stabilization are discussed.
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References
T. Loftsson and M.E. Brewster: J. Pharm. Sci. 85, 1017 (1996).
G. Thomas: Medicinal Chemistry: an Introduction, J. Wiley & Sons, Toronto (2000).
W. Saenger, J. Jacob, K. Gessler, T. Steiner, D. Hoffmann, H. Sanbe, K. Koizumi, S.M. Smith, and T. Takaha: Chem. Rev. 98, 1787 (1998).
K.A. Connors: Chem. Rev. 97, 1325 (1997).
O.S. Tee: Adv. Phys. Org. Chem. 29, 1 (1994).
T. Nagai: Comprehensive Supramolecular Chemistry, Vol. 3, Pergamon/ Elsevier: Oxford (1996).
C.H. Evans and T. Gunnlaugsson: J. Photochem. Photobiol. A: Chem. 78, 57 (1994).
R. Breslow: Acc. Chem. Res. 28, 146 (1995).
P. Bortolus and S. Monti: In D.C. Neckers, D.H. Volman and G. von Bünau (eds.), Advances in Photochemistry, John Wiley & Sons, New York (1996), Vol. 27, p 1.
M. Partyka, H.A. Bao, and C.H. Evans: J. Photochem. Photobiol. A: Chem. 140, 67 (2001).
N. Funasaki, S. Ishikawa, and S. Neya: J. Pharm. Sci. 90, 740 (2001).
K. Uekama, F. Hirayama, and T. Irie: Chem. Rev. 98, 2045 (1998).
V.J. Stella, V.M. Rao, E.A. Zabbou, and V. Zia: Adv. Drug Delivery Rev. 36, 3 (1999).
T. Irie and K. Uekama: Adv. Drug Deliv. Rev. 36, 101 (1999).
D.C. Bibby, N.M. Davies, and I.G. Tucker: Int. J. Pharmaceutics 197, 1 (2000).
T. Loftsson, A. Magnusdottir, M. Masson, and J.F. Sigurjonsdottir: J. Pharm. Sci. 91, 2307 (2002).
J. Luengo, A. Aránguiz, J. Sepúlveda, L. Hernández, and C. Von Plessing: J. Pharm. Sci. 91, 2593 (2002).
V.M. Rao and V. Stella: J. Pharm. Sci. 92, 927 (2003).
M. Masson, T. Loftsson, S. Jonsdottir, H. Fridriksdottir, and D.S. Petersen: Int. J. Pharmacutics 164, 45 (1998).
T. Loftsson: Drug Stability 1, 22 (1995).
M.V. Encinas, E.A. Lissi, and A.M. Rufs: Photochem. Photobiol. 57, 603 (1993).
C.H. Evans, S. De Feyter, L. Viaene, J. van Stam, and F.C. De Schryver: J. Phys. Chem. 100, 2129 (1996).
J. van Stam, S. De Feyter, F. C. De Schryver, and C.H. Evans: J. Phys. Chem. 100, 19959 (1996).
T.C. Barros, K. Stefaniak, J.F. Holzwarth, and C. Bohne: J. Phys. Chem. A 102, 5639 (1998).
M. Christoff, L.T. Okano, and C. Bohne: J. Photochem. Photobiol. A: Chem. 134, 169 (2000).
C.H. Evans, M. Partyka, and J. van Stam: J. Inclusion Phenom. 38, 381 (2000).
A. Muñoz de la Peña, T.T. Ndou, J.B. Zung, K.L. Greene, D.H. Live, and I.M. Warner: J. Am. Chem. Soc. 113, 1572 (1991).
H.C.B. Yang: J. Phys. Chem. 100, 14533 (1996).
T. Yorozu, M. Hoshino, and M. Imamura: J. Phys. Chem. 86, 4426 (1982).
K. Kano, I. Takenoshita, and T. Ogawa: Chem. Lett. 321 (1982).
W.G. Herkstroeter, P.A. Martic, and S. Farid: J. Chem. Soc., Perkin Trans. II 1453 (1984).
J.B. Zung, A. Muñoz de la Peña, T.T. Ndou, and I.M.Warner: J. Phys. Chem. 95, 6701 (1991).
T. Tamaki, T. Kokubu, and K. Ichimura: Tetrahedron 43, 1485 (1987).
S. De Feyter, J. van Stam, F. Imans, L. Viaene, F.C. De Schryver, and C.H. Evans: Chem. Phys. Lett. 277, 44 (1997).
R.A. Agbaria and D. Gill: J. Phys. Chem. 92, 1052 (1988).
R.A. Agbaria and D. Gill: J. Photochem. Photobiol. A 78, 161 (1994).
K.A. Agnew, T.D. McCarley, R.A. Agbaria, and I.M. Werner: J. Photochem. Photobiol. A 91, 205 (1995).
A. Ueno, K. Takahashi, and T. Osa: J. Chem. Soc., Chem. Commun. 921 (1980).
S. Hamai: Bull. Chem. Soc. Jpn. 55, 2721 (1982).
S. Hamai: J. Phys. Chem. 94, 2595 (1990).
S. Hamai, and N. Mononobe: J. Photochem. Photobiol A: Chem. 91, 217 (1995).
S. Hamai: Bull. Chem. Soc. Jpn. 69, 2469 (1996).
S. Hamai: Bull. Chem. Soc. Jpn. 69, 543 (1996).
R.S. Murphy, T.C. Barros, B. Mayer, G. Marconi, and C. Bohne: Langmuir 16, 8780 (2000).
G. Grabner, K. Rechthaler, B. Mayer, and G. Kohler: J. Phys. Chem. A 104, 1365 (2000).
C. Bob: Handbook of Chemistry and Physics, 63rd edn. ed., CRC Press: Boca Raton (1982).
N.J. Turro, M. Aikawa, and A. Yekta: J. Am. Chem. Soc. 101, 772 (1979).
J. Szejtli: Cyclodextrins and Their Inclusion Complexes, Akademiai Kiado: Budapest (1982).
Y. Liao, and C. Bohne: J. Phys. Chem. 100, 734 (1996).
K.A. Connors: Binding Constants Wiley: New York (1987).
S. Hamai: J. Incl. Phenom. Molec. Recog. 27, 57 (1997).
J. Dey, E.L. Roberts, and I.M. Warner: J. Phys. Chem. A 102, 301 (1998).
Z. Yi, C. Zhao, Z. Huang, H. Chen, and H. Yu: Phys. Chem. Chem. Phys. 1, 441 (1999).
M. Ghosh, R. Zhang, R.G. Lawler, and C.T. Seto: J. Org. Chem. 65, 735 (2000).
R. Breslow: Acc. Chem. Res. 24, 159 (1991).
R.P. Rohrbach, L.J. Rodriguez, E.M. Eryring, and J.F. Wojcik: J. Phys. Chem. 81, 944 (1977).
H. Nakamura, A. Sano, and K. Matsuura: Analytical Sciences 14, 379 (1998).
K. Kalyanasundaram: Photochemistry in Microheterogeneous Systems, Academic Press (1987).
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Sau, S., Solanki, B., Orprecio, R. et al. Higher-Order Cyclodextrin Complexes: The Naphthalene System. Journal of Inclusion Phenomena 48, 173–180 (2004). https://doi.org/10.1023/B:JIPH.0000022556.47230.c8
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DOI: https://doi.org/10.1023/B:JIPH.0000022556.47230.c8