title: Spectroscopic studies of inclusion complexes of methyl-p-dimethylaminobenzoate and its ortho derivative with α- and β-cyclodextrins.
abstract: The effects of α- and β-cyclodextrins (CDs) on the both emission modes (LE -locally excited and TICT -twisted intramolecular charge transfer) of the fluorescence spectrum of methyl-p-dimethylaminobenzoate (I) and its o-methoxy (II) derivative in aqueous solution have been investigated using steady-state and time-resolved fluorescence techniques. It is found that the intensity of both fluorescence bands increases with increasing concentration of α- and β-CD. The stoichiometries and equilibrium constants of the fluorophore-cyclodextrin inclusion complexes have been determined by steady-state fluorescence measurements. Performed spectroscopic studies demonstrate that in the case of I in α-CD and β-CD, both 1:1 and 1:2 inclusion complexes are formed, whereas only 1:1 inclusion complex is formed between II and β-CD.
authors: Institute of Experimental Physics, University of Gdańsk, ul. Wita Stwosza 57, 80-952 Gdańsk, Poland.
authors: Agata
authors: A
authors: Lazarowska
authors: Marek
authors: M
authors: Józefowicz
authors: Janina R
authors: JR
authors: Heldt
authors: Józef
authors: J
authors: Heldt
mesh_terms: D010129:4-Aminobenzoic Acid / Q000737:chemistry; D000042:Absorption; D062365:Aminobenzoates / Q000737:chemistry*; D004583:Electrons; D012996:Solutions; D012997:Solvents / Q000737:chemistry; D013050:Spectrometry, Fluorescence; D013997:Time Factors; D047391:alpha-Cyclodextrins / Q000737:chemistry*; D047392:beta-Cyclodextrins / Q000737:chemistry*; D062366:para-Aminobenzoates
chemical_list: D062365:Aminobenzoates; D012996:Solutions; D012997:Solvents; D047391:alpha-Cyclodextrins; D047392:beta-Cyclodextrins; C571498:methyl-p-dimethylaminobenzoate; D062366:para-Aminobenzoates; D010129:4-Aminobenzoic Acid