INTERACTION BETWEEN CYCLODEXTRINS AND AFLATOXINS Q(1), M-1 AND P-1 - FLUORESCENCE AND CHROMATOGRAPHIC STUDIES

The fluorescence properties of the aflatoxins M-1, Q(1), P-1 in soluti on and the effect of various cyclodextrins (alpha-, beta-, gamma-, hyd roxypropyl-beta- and alpha-beta-heptakis-di-O-methyl-beta-) on their f luorescence emission were studied. Among the aflatoxins, a substantial enhancement of the fluorescence emission of aflatoxin Q(1) in the pre sence of aqueous solutions of alpha-, beta-, hydroxypropyl-beta, and a lpha-beta-heptakis-di-O-methyl-beta-cyclodextrin was observed. On the contrary, gamma-cyclodextrin proved to be inefficient to enhance the f luorescence properties of this compound. No important fluorescence enh ancement was found for aflatoxins P-1 or M-1 for any of the cyclodextr in derivatives tested. The complex formation constant (K-f) of these c ompounds with beta-cyclodextrin was chromatographically determined, an d from the results obtained, we can conclude that K-f cannot be used a lone to explain the fluorescence increase. Thermodynamic studies showe d that Delta H and Delta S parameters, associated with the partition o f aflatoxins in RP-HPLC, increased when beta-cyclodextrin was added to the eluent. (C) 1998 Elsevier Science B.V. All rights reserved.