3-benzoxazol-2-yl-7-(N,N-diethylamino)-chromen-2-one as a fluorescence probe for the investigation of micellar microenvironments

It was shown that 3-benzoxazol-2-yl-7-(N,N-diethylamino)-chromen-2-one is suitable to perform as a fluorescent probe, to analyse physical parameters related to organised systems. Micropolarity, microviscosity, critical aggregation and micelle concentration data, in SDS and CTAB micelles, using the proposed compound as fluorescent probe show the compound is allocated, in both micelles, in a strongly polar hydrophilic region (the parameter E-T(30) is equal to 61.3 and 61.9kcal/mol, respectively, in SDS and CTAB micelles, whereas Lippert's Deltaf parameter is equal to 0.35). The CMC of SDS in pure water (7.5 x 10(-3) mol/dm(3)) agrees with the reported values. For SDS and CTAB micelles in buffered medium (PBS buffer, pH 7.4, NaCl 0.9%, w/w), the estimated critical aggregation concentrations (4.6 x 10(-3) and 9.2 x 10(-4) mol/dm(3), respectively, for SDS and CTAB) also agree with the results obtained using equivalent conditions. (C) 2004 Elsevier B.V. All rights reserved.