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Sulfanilamide belongs to the group of drugs that have a bacteriostatic effect on different pathogenic microorganisms. This activity originates from the competitive antagonism with p-aminobenzoic acid, which is an integral part of folic acid. The safe use of sulfanilamide is limited due to poor solubility in the aqueous medium. Therefore, the aim of this paper is the synthesis of sulfanilamide, as well as preparing and structural characterization of its inclusion complexes with cyclodextrins. The crude sulfanilamide was obtained in the synthesis between acetanilide and chlorosulfonic acid according to the standard procedure. The synthesized sulfanilamide was recrystallized from water in order to obtain the satisfactory purity of the substance. Sufanilamide was complexed with beta-cyclodextrin and 2-hydroxypropyl-beta-cyclodextrin by the co-precipitation method. A molecular encapsulation of sulfanilamide was confirmed by using FTIR, H-1-NMR, XRD and DSC methods. Phase-solubility techniques were used to assess the formation of the inclusion complex between sulfanilamide and cyclodextrins. The photostability of sulfanilamide and its inclusion complexes was estimated by UVB irradiation in a photochemical reactor by applying the UV-Vis method. Based on the UV-Vis analysis, sulfanilamide:2-hydroxypropyl-beta-cyclodextrin complex was presented as more photostable than sulfanilamide:beta-cyclodextrin complex and sulfanilamide. The obtained results enable the potential use of these inclusion complexes for the preparation of oral formulations due to the enhanced solubility of sulfanilamide.

Molecular inclusion complexes of usnic acid (UA) with beta-cyclodextrin (beta-CD) and 2-hydroxypropyl beta-cyclodextrin (HP beta-CD) were prepared by the co-precipitation method in the solid state in the molar ratio of 1:1. Structural complexes characterization was based on different methods, FTIR, H-1 NMR, XRD and DSC. Parallel to the complex by the above methods, corresponding physical mixtures of UA with cyclodextrins and complexing agents (beta-CD, HP beta-CD and UA) were analyzed. The results of DSC analysis showed that, at around 200 A degrees C, the endothermal peak in the complexes with cyclodextrins originating from the UA melting has disappeared. Complex diffractogram patterns do not contain peaks characteristic for the pure UA. They are more appropriate to cyclodextrin diffractogram. This fact points to the molecular encapsulation of UA in the cyclodextrin cavity. Chemical shifts in H-1 NMR spectra after the inclusion of UA into the cyclodextrin cavity, especially H-3 protons (0.0012 and 0.0102 ppm in the beta-CD and HP beta-CD, respectively) and H-5 and H-6 (0.0134 ppm) and hydrogen from CH3 (0.0073 ppm) HP beta-CD also points to the formation of molecular inclusion complexes. The improved solubility of UA in water was achieved by molecular incapsulation. In the complex with beta-CD the solubility is 0.3 mg/cm(3), with HP beta-CD 4.2 mg/cm(3) while the uncomplexed UA solubility is 0.06 mg/cm(3). The microbial activity of UA and both complexes was tested against eight bacteria and two fungi and during the test no reduced activity of UA in the complexes was observed.

This paper reports a molecular modeling study of complex formation and aggregation behavior of a supramolecular system comprising three different moieties forming two distinct molecules. One molecule is a phenol derivative of porphyrin conjugated to a macrocyclic oligosaccharide, β-cyclodextrin (β-CD), and the other is 1-adamantanol (ADM). The inclusion complex of the latter molecule with the porphyrin–β-cyclodextrin (β-CD) conjugate, and the dimeric aggregates of the conjugate both in the presence and in the absence of the guest are investigated through molecular mechanics and molecular dynamics methods in vacuo, since the systems are scarcely soluble in polar solvents. In this way, we can find the most likely geometry of the complexes or aggregates and characterize the competitive inclusion behavior of ADM and of a porphyrin phenol within the β-CD cavity in terms of the various energy contributions stabilizing the resulting aggregates and/or inclusion complexes.

International audience; An insoluble polymeric network containing cyclodextrins (CDs) and amino, hydroxyl and carboxylic groups, was used for the detoxification of multicontaminated wastewaters. The comparison of its sorption capacity with that of a similarly prepared starch material showed superior efficiency towards organic compounds, though maintaining the same efficiency towards inorganic species. The incorporation of cyclodextrin cavity into a solid network provides an easy separation of pollutants from water, after their uptake onto the sorbent surface. In fact, the presence of CDs ensures the formation of inclusion complexes enhancing the sorption properties. The proposed sorbent also shows good sorption capacity for cations and other inorganic compounds, which is mandatory for the treatment of multicontaminated wastewaters.

Ochratoxin A (OTA) is a nephrotoxic mycotoxin produced by several fungal species, mainly Aspergillus ochraceus, A. carbonarius and Penicillium verrucosum. It contaminates many foodstuffs, particularly cereals and their derivatives, coffee, beer, wine and cocoa, and represents a serious health threat both to humans and animals. Spectroscopic properties of OTA solutions depend on the pH, solvent polarity and can be influenced by the presence of cyclodextrins (CDs). In this work, the effect of beta-CD on spectroscopic properties of OTA in aqueous solutions has been investigated by means of absorption and steady-state fluorescence at different pHs (range 3.5-9.5). Binding constants of OTA/beta-CD inclusion complexes have been determined by applying modified Benesi-Hildebrand equation. A 1:1 stoichiometry of OTA/beta-CD complexes has been observed at all tested pHs.