Aggregation properties of hydrophobized hyaluronan (hHA) in different molecular weights and degree of substitution were studied by pyrene and perylene fluorescence method. The critical aggregation concentration (cac) was determined by the pyrene I1/I3 and perylene fluorescence intensity method. The value of the cac for the hHA in aqueous solution was measured at different molecular weights and at 293.2 K. The cac value varied both with the molecular weight and the degree of substitution and was between 0.610-0.003 g L?1. Pyrene Polarity Scale confirmed formation of hydrophobic domains of the relative hydrophobic index about 0.85.Studium agregace hydrofobizovaného hyaluronanu ve vodném prostředí s využitím fluorescenčních sond jako detekčníh...