The fluorescence enhancement of the probe molecule 1-anilino-8-naphthalenesulfonate (ANS) by a number of modified beta-cyclodextrins has been studied. Alkyl-and hydroxyalkyl-substituted beta-cyclodextrins show significantly greater enhancement of ANS fluorescence than does the parent unmodified beta...

Addition of hydroxypropyl-beta-cyclodextrin to o-phthalaldehyde (OPA)-amino acid-thiol reaction mixtures is shown to cause significant enhancement of the fluorescence of the isoindole product for a wide range of amino acids, with the largest effects observed in the cases of glycine and lysine. The l...

The fluorescent molecules 1-anilinonaphthalene-8-sulfonate (1,8-ANS) and 2-anilinonaphthalene-6-sulfonate (2,6-ANS) are extremely sensitive to the polarity of their local environment, making them excellent probes for the study of heterogeneous systems, including cyclodextrin (CD) solutions. Both are...

The fluorescence intensity of 7- methoxycoumarin (7MC) in aqueous solution is found to significantly decrease upon addition of various cyclodextrins. This observed phenomenon is described as fluorescence suppression, to distinguish it from fluorescence reduction via bimolecular quenching. The decrea...

Laser flash photolysis of 9-hydroxy-9-fluorenecarboxylic acid in hexafluoro-2-propanol (HFIP) generates a transient with lambda(max) at 495 nm that reacts with nucleophiles such as methanol and bromide and is insensitive to oxygen. In the presence of 0.15 M trifluoroacetic acid, a different transien...

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The polarity-sensitive fluorescent dye Nile Red forms association complexes with various cyclodextrins in aqueous solution. The formation of such association complexes has a significant effect on the Nile Red fluorescence, with the largest effect being observed in gamma-cyclodextrin solution. When g...

The effect of alpha-, beta-, and gamma-cyclodextrin (CD) and their hydroxygropylated (HP) derivatives on the solubility and fluorescence of the compound curcumin has been studied. Curcumin, the main constituent of the Indian spice turmeric, is of growing interest due to its wide-ranging pharmaceutic...

We report the first use of fluorescence spectroscopy to probe the environment of the cavities that are present in open framework coordination polymers.

The effect of the macrocyclic host compounds cucurbit[n]urils (Qn), with n = 5 - 7, on the fluorescence of the biologically active compound curcumin has been studied. Curcumin, the main constituent of the Indian spice turmeric, is of growing interest because of its wide-ranging pharmaceutical proper...

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The macrocyclic ligand cyclam occurs as a 70:30 mixture of its trans-I and trans-II configurations, respectively, when included as its CuII complex inside the cavity of the macrocyclic host compound cucurbit[8]uril. This is the first report of an unsubstituted cyclam occurring in either of these two...

Azinphos-methyl (AZM) is a widely used organophosphate insecticide and acaricide, with demonstrated negative impacts on the environment. Upon absorption of UV-A radiation, this molecule undergoes photolysis to the highly fluorescent compound N-methylanthranilic acid, which undergoes subsequent photo...

Various methods for the enhancement of the fluorescence of the pesticide azinphos-methyl are reported. The addition of hydroxypropyl-beta-cyclodextrin was found to moderately enhance the fluorescence by a factor of three, presumably via inclusion of the pesticide into the cyclodextrin cavity. This c...

Fluorescence enhancement of a probe molecule in solution by the container molecule cucurbituril (CB) is reported for the first time. The fluorescence of the probe 2-anilinonaphthalene-6-sulfonate (2,6-ANS) in aqueous Na2SO4 solution is found to increase by a maximum factor of 5.0 upon addition of cu...

The ketene derived from diazoquinone 5 can be readily detected by laser photolysis techniques with IR detection and its behavior agrees with that observed with more conventional UV-visible detection. The ketene reacts with amines (e.g. k similar to 7 x 10(7) M-1 s(-1) for diethylamine) to give ylide...

The C=O stretching vibration appears in the infrared spectra of 2-naphthaldehyde (1), 2-acetonaphthone (2), 2-naphthoic acid (3), methyl 2-naphthoate (4) and 1,2-dihydro-3H-benz[e]inden-3-one (5) in the state T-1(pi pi*) between 1600 and 1700 cm(-1). There is a strong line in the Raman spectrum of 1...

The S-1 population decay times of azulene and 1,4-dimethyl-7-isopropylazulene (guaiazulene) in solution have been determined as a function of their initial vibrational energy content, E(vib)(i), using a pump-probe experiment with subpicosecond time resolution. The S-1 lifetime of azulene does not de...

The reactivity of the azidyl radical (N-3(.)) With olefins has been studied in acetonitrile solution using time-resolved UV-vis and infrared (TRIR) laser flash photolysis techniques. Azidyl radicals, formed by electron transfer from azide to excited state ketones, combine with excess azide in aceton...

Semianalytic perturbative approaches for investigating the spectroscopy, and the underlying dynamics, associated with fast time-resolved, two-photon, two-color, pump-probe, low intensity laser-molecule interactions are developed and discussed. In particular the perturbation theory is developed with ...

The S1 population decay times of azulene and 4,6,8-trimethylazulene have been measured in solvents with a wide range of viscosities using a two-photon, two-color, pump-probe method. The S, lifetimes vary as expected on the basis of the energy gap law. No effect of solvent viscosity is observed, cont...