The possibility of using pyrene as a fluorescent probe in a model chemosensor composed of β-cyclodextrin–pyrene (Py– β CD) complex in aqueous solution was studied in the presence of several analytes (A) of different polarity. Absorption bands that prove the formation of the aggregated Py– β CD complex were found in the UV–VIS spectra of aqueous solution of pyrene with added β CD. The aggregate size as measured by dynamic light scattering was found to have a value of 3.2–3.6 nm. The aggregate was identified as a 1:2 complex of Py with β CD (Py@2 β CD) surrounded by two empty β CD molecules. The ratio I 3 / I 1 of intensity I 3 of the third vibronic band at ~26,000 cm −1 in the fluorescence spectrum to intensity I 1 of the 0–0 transition at ~26,800 cm −1 was used as an analytical characteristic of the fluorescent probe. The value of I 3 / I 1 for Py@2 β CD is highly sensitive to the presence of several μM of analyte in aqueous solution, and this value is markedly higher than that for pyrene in solution.
