RT info:eu-repo/semantics/article T1 Improvement of water solubility of sulfamethizole through its complexation with ß- and hydroxypropyl-ß-cyclodextrin - Characterization of the interaction in solution and in solid state A1 Echezarreta López, María Magdalena A1 Pose-Vilarnovo, Beatriz A1 Perdomo-López, Iliana A1 Schroth-Pardo, Patricia A1 Estrada, Ernesto A1 Torres-Labandeira, Juan J. A2 Ingeniería Química y Tecnología Farmacéutica K1 Sulfamethizole K1 b-Cyclodextrin K1 Hydroxypropyl-b-cyclodextrin K1 NMR K1 Molecular modelling K1 Dissolution AB The aim of this study was to increase the solubility of sulfamethizole in water by complexing it with b-cyclodextrin (BCD) and hydroxypropyl-b-cyclodextrin (HPBCD). The interaction of sulfamethizole with the cyclodextrins was evaluated by the solubility, H NMR spectrometry and molecular modelling. The stability constants calculated from the phase solubility method increase in order HPBCD,BCD. From the NMR studies could be concluded that the sulfamethizole:cyclodextrin mole ratio was 1:1 (mol/mol) in the BCD complex and 2:3 (mol/mol) in the HPBCD complex. In both cases the sulfamethizole moiety included in the cyclodextrin was the thiadiazole group. MM2 calculations, either in vacuum or in the presence of a solvent, support this structure. Solid inclusion complexes of sulfamethizole with BCD and HPBCD were obtained by freeze drying 1:1 (mol/mol) solutions in aqueous ammonium hydroxide. Host–guest interactions were studied in the solid state by powder X-ray diffractometry and differential scanning calorimetry. The dissolution rates of sulfamethizole increased by the complexation with BCD or HPBCD YR 2001 FD 2001 LK http://riull.ull.es/xmlui/handle/915/37311 UL http://riull.ull.es/xmlui/handle/915/37311 LA en NO Financiado por Xunta de Galicia under project PGIDT99-PXI20305B DS Repositorio institucional de la Universidad de La Laguna RD 18-ene-2025