Supramolecular Organisation of Oligomeric Hyaluronans in Aqueous Environments and Its Change During Chemical Modification

To study conformational changes in oligomeric hyaluronan (HN) macromolecules (11.2-50.0 kDa) in aqueous solutions over a wide pH range (4.0-10.0), 2-aminobenzoic ac-id-labeled macromolecules of the polysaccharide were synthesized. The main macromo-lecular chain stability during the process of the label to HN conjugation was confirmed by the solutions viscosity permanence. To verify the HN molecules modification, Fluores-cence Spectrophotometry (FS) and Hydrophilic Interaction High-Performance Liquid Chromatography (HILIC HPLC) with fluorimetric detection were used. The conforma-tional behavior of labeled HNs was studied with Differential Scanning Fluorimetry (DSF), and the average hydrodynamic sizes of particles were estimated with Dynamic Light Scattering (DLS) and Nanoparticle Tracking Analysis (NTA). The change in the label flu-orescence intensity and the particle sizes of both the original labeled HNs and the prod-ucts of their chemical interaction with n-Butanediol diglycidyl ether (BDDE) were as-sessed. Assumptions regarding the direction of the chemical interaction processes of HNs and glycidyl ethers were made.