TURBIDIMETRY AND FLUORESCENCE STUDY OF HYALURONAN-SURFACTANT NANOPARTICLES FORMATION

This paper deals with electrostatic association of cationic micelles (CTAB or Septonex) with hyaluronan. Hyaluronan as negatively charged polyelectrolyte can interact with positively charged surfactant micelles via electrostatic interactions to form nano-core-shell like aggregates. These self-assembly nanoparticles can solubilize hydrophobic active substances and therefore, they are potential carriers in drug delivery applications. The cationic micelle/hyaluronan complexes were studied using turbidimetry and fluorescence spectroscopy method. Turbidimetric titration was chosen as an indicator of component aggregation which is related to the loss of transmitted light intensity due to the scattering effect. Fluorescent probe pyrene was selected for spectroscopy experiments because of its unique sensitivity to polarity of the medium, so this fluorescence method was used as an indicator of presence of hydrophobic domains in the system. Effect of components concentration and molecular weight of hyaluronan were evaluated. Results of turbidimetry revealed that aggregates formation (turbidity increasing) depends especially on a charge ratio of surfactant molecules and hyaluronan carboxyl groups. It was found a difference in association of low molecular weight and high molecular weight of hyaluronan. Fluorescence results confirmed presence and stability of micellar aggregates in studied systems.