Supramolecular architecture of betulin diacetate complexes witharabinogalactan from Larix sibirica

Abstract

tSupramolecular ensembles of arabinogalactan (AG) and its complexes with betulin diacetate (BDA) werestudied in water and dimethyl sulfoxide (DMSO) using ablation, induced by submillimeter radiation fromthe free electron laser. Solutions of 1 wt% AG resulted in formation of aerosol particles with a maximumsize of 60–70 nm. In contrast, with DMSO as the solvent, the majority of particles were significantlysmaller. Nevertheless, the addition of water shifted the particle size distribution to a larger size, suggestingthe cross-linking of AG chains due to hydrogen bonding through water molecules. The ensembles ofmolecules were larger in solutions of the AG–BDA complex as compared to pure AG aqueous solution,and the distribution was narrow. The role of side chain interactions in the formation of AG–BDA complexesin aqueous solutions was confirmed by NMR.