Fluorescence, induced circular dichroism and molecular mechanics of 1-methyl naphthalenecarboxylate complexes with 2-hydroxypropyl cyclodextrins.

Steady-state, time-resolved fluorescence, Circular Dichroism and Molecular Mechanics techniques were used to study the complexation of 1-methyl naphthalenecarboxylate (1MN) with the 2-hydroxylpropyl-alpha-, -beta- and -gammacyclodextrins (HPCDs). The emission spectrum of 1MN shows two bands whose intensity ratios (R) are sensitive to complexation. The stoichiometry, binding constants and thermodynamics parameters upon complexation were obtained from the variation of fluorescence intensity, R, and lifetime averages, [Formula: see text], with [HPCD] and temperature.

Inclusion complexes of a bichromophoric diester containing anthracene and naphthalene groups with alpha- and beta-cyclodextrins: thermodynamics and molecular mechanics.

Fluorescence and molecular mechanics have been used to study the inclusion complexes of the (9-anthryl)-COO-(CH2)2-OOC-(2-naphthyl) bichromophoric compound with alpha- and beta-cyclodextrins. Emission spectra upon excitation of the naphthalene group denote the presence of non-radiative energy transfer from naphthalene to anthracene, which is influenced by the type of CD. Naphthalene emission also shows two peaks whose ratio of intensities R is sensitive to the medium polarity.

Thermodynamics of complexation of dimethyl esters of tere-, iso-, and phthalic acids with alpha- and beta-cyclodextrins.

Thermodynamics of inclusion of alpha- and beta-cyclodextrins (CDs) with three diester precursors of polyesters, dimethyl terephthalate (DMT), dimethyl isophthalate (DMI), and dimethyl phthalate (DMP) were studied with different fluorescence spectroscopy techniques. The stoichiometry, association constants, and other thermodynamics parameters were investigated from the fluorescence intensity decrease that takes place upon CD addition and temperature changes. Apart from DMP, which did not form a complex with alphaCD, all other systems showed 1:1 stoichiometry complexes with different stabilities.