Fluorescence studies of pyrene inclusion complexes with .alpha.-, .beta.-, and .gamma.-cyclodextrins in aqueous solutions. Evidence for formation of pyrene dimer in .gamma.-cyclodextrin cavity

1982 ◽  
Vol 86 (22) ◽  
pp. 4426-4429 ◽  
Author(s):  
Takehiko Yorozu ◽  
Mikio Hoshino ◽  
Masashi Imamura
Keyword(s):  
Aqueous Solutions ◽  
Inclusion Complexes ◽  
Fluorescence Studies ◽  
Cyclodextrin Cavity ◽  
Alpha Beta ◽  
Gamma Cyclodextrin

Photoexcited inclusion complexes of .beta.-naphthol with .alpha.-, .beta.-, and .gamma.-cyclodextrins in aqueous solutions

1982 ◽  
Vol 86 (22) ◽  
pp. 4422-4426 ◽  
Author(s):  
Takehiko Yorozu ◽  
Mikio Hoshino ◽  
Masashi Imamura ◽  
Haruo Shizuka
Keyword(s):  
Aqueous Solutions ◽  
Inclusion Complexes ◽  
Alpha Beta

scholarly journals Water inside β-cyclodextrin cavity: amount, stability and mechanism of binding

2019 ◽  
Vol 15 ◽  
pp. 1592-1600 ◽  
Author(s):  
Stiliyana Pereva ◽  
Valya Nikolova ◽  
Silvia Angelova ◽  
Tony Spassov ◽  
Todor Dudev
Keyword(s):  
Inclusion Complexes ◽  
Water Clusters ◽  
Bound Water ◽  
Thermodynamic Characteristics ◽  
Water Molecules ◽  
Native State ◽  
Hydrophobic Substances ◽  
Cyclodextrin Cavity ◽  
Stabilizing Factors ◽  
Native Host

Cyclodextrins (CDs) are native host systems with inherent ability to form inclusion complexes with various molecular entities, mostly hydrophobic substances. Host cyclodextrins are accommodative to water molecules as well and contain water in the native state. For β-cyclodextrin (β-CD), there is no consensus regarding the number of bound water molecules and the location of their coordination. A number of intriguing questions remain: (1) Which localities of the host’s macrocycle are the strongest attractors for the guest water molecules? (2) What are the stabilizing factors for the water clusters in the interior of β-CD and what type of interactions between water molecules and cavity walls or between the water molecules themselves are dominating the energetics of the β-CD hydration? (3) What is the maximum number of water molecules inside the cavity of β-CD? (4) How do the thermodynamic characteristics of β-CD hydration compare with those of its smaller α-cyclodextrin (α-CD) counterpart? In this study, we address these questions by employing a combination of experimental (DSC/TG) and theoretical (DFT) approaches.

Interaction of native cyclodextrins and their hydroxypropylated derivatives with parabens in aqueous solutions. Part 1: evaluation of inclusion complexes

2019 ◽  
Vol 93 (3-4) ◽  
pp. 309-321 ◽  
Author(s):  
André Rodrigues Sá Couto ◽  
Sara Aguiar ◽  
Alexey Ryzhakov ◽  
Kim Lambertsen Larsen ◽  
Thorsteinn Loftsson
Keyword(s):  
Aqueous Solutions ◽  
Inclusion Complexes

Chromatography of alpha-, beta- and gamma-Cyclodextrin on Dextran Gel Columns

1978 ◽  
Vol 30 (8) ◽  
pp. 276-279 ◽  
Author(s):  
B. Zsadon ◽  
M. Szilasi ◽  
J. Szejtli ◽  
G. Seres ◽  
F. Tüdös
Keyword(s):  
Alpha Beta ◽  
Gamma Cyclodextrin

Heteroassociation of meso-sulfonatophenylporphyrins with β- and γ-cyclodextrin

2001 ◽  
Vol 05 (05) ◽  
pp. 465-473 ◽  
Author(s):  
ZOUBIR EL-HACHEMI ◽  
JOAN-ANTON FARRERA ◽  
HECTOR GARCÍA-ORTEGA ◽  
OSCAR RAMÍREZ-GUTÍERREZ ◽  
JOSEP M. RIBÓ
Keyword(s):  
Inclusion Complexes ◽  
Bulk Water ◽  
Hydrophobic Region ◽  
Water Solutions ◽  
H Nmr ◽  
Cyclodextrin Inclusion Complexes ◽  
Cyclodextrin Inclusion ◽  
Cyclodextrin Cavity ◽  
Nuclear Overhauser ◽  
Derivatives Of

The effect of the addition of β- and γ-cyclodextrin (β-CD, γ-CD) to water solutions ( D 2 O ) of the 4'-sulfonato derivatives of meso-tetraphenylporphyrin (TPPS4, TPPS3, TPPS2o and TPPS2a) was studied by 1 H NMR at several temperatures. In all cases the disaggregation of the porphyrin homoassociates was detected, although in most cases it was only partial. Nuclear Overhauser signals (ROESY) show that cyclodextrin inclusion complexes were formed with TPPS4, TPPS3, and TPPS2o, but not with TPPS2a. These complexes include the sulfonatophenyl groups as guest, but not the hydrophobic phenyl substituents. The geometry of the complexes corresponds to that in which the sulfonatophenyl substituent is introduced through the secondary face of β-CD and through the primary face of γ-CD. In the inclusion complexes the polar sulfonato group is inside the cyclodextrin cavity but near to the hydrophilic interface with the bulk water. This explains the absence of complexation in the case of cationic porphyrins such as 5,10,15,20-tetrakis(N-methylpyridin-4-yl)porphyrin (TMPyP), and the decrease in the solubility when the β-CD complex of 5,15-bis(4-sulfonatophenyl)porphyrin (DPPS2o) forms. Complexes of the cyclodextrins with porphyrin homoassociates were also detected. This indicates that the heteroassociation avoids the formation of staggered stacks of porphyrin homoassociates, but has less effect on the association through the hydrophobic region of the phenyl substituents. This last type of aggregation, which is not significantly affected by the addition of α-CD, explains why the hydrophobic phenyl substituents are not complexed by the cyclodextrins.

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