Fluorescent properties of merocyanine 540 in solutions of sialogangliosides.

The spectral modifications in the absorption and emission properties of merocyanine 540 have been evaluated in solvents of varying dielectric constants. The fluorescence behavior of dye in solutions of low dielectric constant has offered a possibility for monitoring the micropolarity of sialoganglioside micelles in aqueous solutions. Our results demonstrate that sialic acid residues markedly influence the aggregation properties of gangliosides in solution as well as the nature of dye binding to the micellar structures.