Association of aescin with β- and γ-cyclodextrins studied by DFT calculations and spectroscopic methods

• Ana I. Ramos,
• Pedro D. Vaz,
• Susana S. Braga and
• Artur M. S. Silva

Beilstein J. Nanotechnol. 2017, 8, 348–357, doi:10.3762/bjnano.8.37

• Santiago, 3810-193 Aveiro, Portugal 10.3762/bjnano.8.37 Abstract Background: Aescin, a natural mixture of saponins occurring in Aesculus hippocastanum, exhibits important flebotonic properties, being used in the treatment of chronic venous insufficiency in legs. The inclusion of aescin into cyclodextrins

• (CDs) is a technical solution for its incorporation into the textile of stockings, but details of the physicochemistry of these host–guest systems are lacking. This work investigates the inclusion of aescin into the cavities of two native cyclodextrins, β-CD and γ-CD. Results: The continuous variation

• method applied to aqueous-phase 1H nuclear magnetic resonance (1H NMR) has demonstrated that the preferred CD/aescin inclusion stoichiometries are 2:1 with β-CD and 1:1 with γ-CD. The affinity constant calculated for γ-CD·aescin was 894 M−1, while for 2β-CD·aescin it was estimated to be 715 M−1. Density