caa a22 4500 445328509 CHVBK 20180317142729.0 cr unu---uuuuu 170323e20110901xx s 000 0 eng 10.1007/s10953-011-9724-0 doi (NATIONALLICENCE)springer-10.1007/s10953-011-9724-0 Inclusion Complex Formation Between Modified Cyclodextrins and Riboflvin and Alloxazine in Aqueous Solution [Elektronische Daten] [Irina Terekhova, Malgorzata Koźbiał, Roman Kumeev, Gennady Alper] Inclusion complex formation of hydroxypropylated α-, β- and γ-cyclodextrins with riboflavin (vitamin B2) and alloxazine was studied by spectroscopic and solubility methods. Alloxazine, which is a structural analog of riboflavin, was considered in order to evaluate the role of ribityl and methyl substituents in complexation. Thermodynamic parameters for 1:1 complex formation were obtained and analyzed in terms of influence of the reagent structure on the binding process. It was shown that the cavity of hydroxypropyl-β-cyclodextrin is more appropriate for formation of stable complexes. The complexes are enthalpy stabilized, due to prevalence of van der Waals interactions and possible hydrogen bonding. The partial insertion of riboflavin into the cyclodextrin cavity was revealed by 1H NMR and computer modeling. The ribityl side chain, which prevents deep inclusion, is located nearby the wider rim of the cyclodextrin molecule and can undergo destruction. Penetration of the alloxazine molecule into the macrocyclic cavity is deeper and accompanied by formation of more stable inclusion complexes. Hydroxypropyl-β-cyclodextrin was found to be the more efficient solubilizing agent for riboflavin and alloxazine, whereas a stabilization action of cyclodextrins towards riboflavin was not observed. Springer Science+Business Media, LLC, 2011 Inclusion complex nationallicence Modified cyclodextrins nationallicence Riboflavin nationallicence Alloxazine nationallicence Thermodynamics nationallicence Terekhova Irina Institute of Solution Chemistry of Russian Academy of Sciences, 1 Akademicheskaya Str., 153045, Ivanovo, Russian Federation aut Koźbiał Malgorzata Institute of Physical Chemistry of Polish Academy of Sciences, 44/52 Kasprzaka, 01-224, Warsaw, Poland aut Kumeev Roman Institute of Solution Chemistry of Russian Academy of Sciences, 1 Akademicheskaya Str., 153045, Ivanovo, Russian Federation aut Alper Gennady Institute of Solution Chemistry of Russian Academy of Sciences, 1 Akademicheskaya Str., 153045, Ivanovo, Russian Federation aut Journal of Solution Chemistry Springer US; http://www.springer-ny.com 40/8(2011-09-01), 1435-1446 0095-9782 40:8<1435 2011 40 10953 https://doi.org/10.1007/s10953-011-9724-0 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s10953-011-9724-0 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Terekhova Irina Institute of Solution Chemistry of Russian Academy of Sciences, 1 Akademicheskaya Str., 153045, Ivanovo, Russian Federation aut NATIONALLICENCE 700 1- Koźbiał Malgorzata Institute of Physical Chemistry of Polish Academy of Sciences, 44/52 Kasprzaka, 01-224, Warsaw, Poland aut NATIONALLICENCE 700 1- Kumeev Roman Institute of Solution Chemistry of Russian Academy of Sciences, 1 Akademicheskaya Str., 153045, Ivanovo, Russian Federation aut NATIONALLICENCE 700 1- Alper Gennady Institute of Solution Chemistry of Russian Academy of Sciences, 1 Akademicheskaya Str., 153045, Ivanovo, Russian Federation aut NATIONALLICENCE 773 0- Journal of Solution Chemistry Springer US; http://www.springer-ny.com 40/8(2011-09-01), 1435-1446 0095-9782 40:8<1435 2011 40 10953 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer