Preparation and study on the novel solid inclusion complex of ciprofloxacin with HP-beta-cyclodextrin

The interaction of ciprofloxacin with HP-beta-cyclodextrin (HP-beta-CD) has been studied by several analytical techniques, including 1H nuclear magnetic resonance (NMR), 13C NMR, fluorescence spectra, infrared spectroscopy, thermal analyzer and scanning electron microscope. In this paper, solid inclusion complex of ciprofloxacin with HP-beta-CD was synthesized by the coprecipitation method. In addition, the characterization of the inclusion complex has been proved by fluorimetry, infrared, differential scanning calorimetry and one-dimensional (1D), 2D NMR. The experimental results confirmed the existence of 1:1 inclusion complex of ciprofloxacin with HP-beta-CD. The formation constant of complex was determined by fluorescence method and 1H NMR. Spacial configuration of complex has been proposed on two-dimensional NMR technique.     

Preparation and study on the solid inclusion complex of sparfloxacin with beta-cyclodextrin

The interaction of sparfloxacin with beta-cyclodextrin (beta-CD) has been studied by several analytical techniques, including 1H-NMR, 13C-NMR, fluorescence spectroscopy, infrared spectroscopy, thermal analysis, and scanning electron microscope. In this paper, solid inclusion complex of sparfloxacin with beta-CD was synthesized by the coprecipitation method. In addition, the characterization of the inclusion complex has been proved by fluorimetry, Infrared, differential scanning calorimetry and 1D, 2D NMR. The experimental results confirmed the existence of 1:1 inclusion complex of sparfloxacin with beta-CD. The formation constant of complex was determined by fluorescence method and 1H-NMR. Spacial configuration of complex has been proposed on 2D NMR techniques.     

Preparation and study on the solid inclusion complex of ciprofloxacin with beta-cyclodextrin

The interaction of ciprofloxacin with beta-cyclodextrin (betaCD) has been studied by several analytical techniques, including 1H-NMR (nuclear magnetic resonance),13C-NMR, fluorescence spectroscopy, infrared (IR) spectroscopy, thermal analysis, and scanning electron microscope. In this paper, solid inclusion complex of ciprofloxacin with beta-CD was synthesized by the coprecipitation method. In addition, the characterization of the inclusion complex has been proved by fluorimetry, IR, differential scanning calorimetry and 1D, 2D NMR. The experimental results confirmed the existence of 1:1 inclusion complex of ciprofloxacin with beta-CD. The formation constant of complex was determined by fluorescence method and 1H-NMR. Spatial configuration of complex has been proposed on two dimensional NMR technique.     

Preparation and study on the solid inclusion complex of cloxacillin sodium with beta-cyclodextrin

The interaction of cloxacillin sodium with beta-cyclodextrin (beta-CD) has been studied by several analytical techniques, including (1)H NMR, fluorescence spectroscopy, infrared spectroscopy. In this paper, solid inclusion complex of cloxacillin sodium with beta-CD was synthesized by the coprecipitation method. In addition, the characterization of the inclusion complex has been proved by fluorimetry, infrared spectroscopy and 1D, 2D NMR. The experimental results confirmed the existence of 1:1 inclusion complex of cloxacillin sodium with beta-CD. The formation constant of complex was determined by fluorescence method and (1)H NMR. Spacial configuration of complex has been proposed on 2D NMR technique.     

Preparation and physicochemical characterization of omeprazole:methyl-beta-cyclodextrin inclusion complex in solid state

In this work, we illustrate the usefulness of cyclodextrins, namely, methyl-β-cyclodextrin (MβCD), an amorphous, methylated derivative of the natural β-cyclodextrin (βCD), as a tool to form an inclusion complex with omeprazole (OME), a poorly water soluble drug. Solid binary systems between OME and MβCD were prepared experimentally in a stoichiometry 1:1 by different techniques (physical mixing, kneading, spray-drying and freeze-drying). Afterward these products were characterized by Fourier transformation-infrared spectroscopy (FTIR); X-ray diffractometry (XRD) and scanning electron microscopy (SEM). The results obtained suggest that spray-drying and freeze-drying methods yield a higher degree of amorphous entities suggesting the formation of inclusion complexes between OME and MβCD.     

Preparation and property screening of the solid inclusion complex of norfloxacin with p-sulfonated calix[4]arene

The complexation of norfloxacin (NFLX) by p-sulfonated calix[4]arene (SC4A) in aqueous solution has been studied by fluorescence spectroscopy and 1H NMR spectroscopy. A 1:1 stoichiometry and a 8086 L mol(-1) stability constant of the NFLX-SC4A complex was obtained by spectrofluorometric titrations. The equimolar solid state inclusion complex of NFLX-SC4A was prepared by the co-precipitation method and then characterized by various techniques, including differential scanning calorimetry (DSC), X-ray powder diffractometry (XRD), Fourier-transform infrared analysis (FT-IR) and scanning electron microscopy (SEM). The experimental results of these chemical property screenings confirmed that NFLX and SC4A can form a stable host-guest complex in the solid state, and SC4A appears to function as a complexing and solubilizing agent for NFLX.     

Study on the inclusion behavior and solid inclusion complex of 5-amino-6-methyl-2-benzimidazolone with cyclodextrins

The inclusion behaviors of three native or modified CDs including p-CD,2-hydroxypropyl-β-CD(2-Hp-β-CD) and 2,6-dimethyl-β-CD(Me-β-CD) toward 5-amino-6-methyl-2-benzimidazolone(AMBI) were comparatively investigated by NMR and fluorescence titration in combination with IR spectra,X-ray diffractometry and scanning electron microphotographs.The experimental results jointly demonstrated that the phenyl ring of AMBI entered into the cavity of the CDs and located close to the narrow rims accompanied by the formation of the 1:1 inclusion complex with large stability constant in aqueous solution.The introduction of the hydroxypropyl unit to the host improved the solubility,ultimately effecting an obvious promoting in the fluorescence intensity and the stability constant     

Preparation and spectroscopic studies of an inclusion complex of adenine with beta-cyclodextrin in solution and in the solid state

The interaction between adenine and beta-CD has been investigated in solution and in the solid state by several analytical techniques, primarily by 1H-NMR, 2D ROESY and fluorescence spectra, and secondarily by other important techniques, for example, Fourier transform infrared spectroscopy (FT-IR) and differential scanning calorimetry (DSC). The association constant and 1:1 nature of the complex between adenine and beta-CD in solution were determined by fluorescence spectroscopy. A spatial configuration for the complex in solution is proposed from analysis of the 1H-NMR and 2D ROESY data. The Fourier transform infrared spectroscopy (FT-IR) and differential scanning calorimetry (DSC) data are consistent with the formation of an inclusion complex. In addition, a solid inclusion complex of adenine with beta-CD was synthesized by the coprecipitation method.     

Preparation and spectral investigation on inclusion complex of beta-cyclodextrin with rutin

Solid inclusion complex of rutin with beta-cyclodextrin (beta-CD) was prepared by coprecipitate method. The formation of inclusion complex was confirmed by differential scanning calorimetry (DSC) and X-ray diffraction. The formation constant was obtained by steady-state fluorescence measurements and the result suggested the complex preferred 1:1 (rutin:CD) stoichiometry. Furthermore, the spatial configuration of the complex has been proposed based on NMR and molecular modeling.     

Preparation and characterization of theβ-cyclodextrin inclusion complex with phenylpropiolic acid

The preparation of a 1:1 complex involving-cyclodextrin (-CD) and phenylpropiolic acid (PPA) is reported. The new inclusion complex of-CD has been characterized on the basis of its chemical analysis, thermal behavior, infrared spectrum, X-ray powder pattern and¹³C-NMR spectrum in DMSO solution.     

Preparation and study on the inclusion complexes of two tanshinone compounds with beta-cyclodextrin

Solid inclusion complexes of two tanshinones (Tans): tanshinone IIA (Tan IIA), tanshinone I (Tan I) with beta-cyclodextrin (beta-CD) were synthesized by coprecipitation method. The solid inclusion complexes were characterized by using several analytical techniques: (1)H NMR spectra, IR spectra and thermal analysis. Stoichiometry of the inclusion complexes of Tans with beta-CD or HP-beta-CD is 1:1 which was investigated in solution. The formation constants of the complexes were determined by UV spectrophotometry. For same kind of CD, the stability was in the order: Tan IIA > Tan I; for same guest, the stability was in the order: HP-beta-CD > beta-CD. The effect of temperature on the inclusion interaction was examined and the thermodynamic parameters of inclusion process, Delta G, Delta H, Delta S were determined as well. The experimental results indicate that the inclusion process was an exothermic and enthalpy-driven process accompanied with a negative entropic contribution. The inclusion interaction between CD and Tans satisfied the law of enthalpy-entropy compensation.     

Preparation and spectral investigation of inclusion complex of caffeic acid with hydroxypropyl-beta-cyclodextrin

The inclusion complexation behavior of caffeic acid (CA) with hydroxypropyl-beta-cyclodextrin (HP-beta-CD) was studied by UV-vis, fluorescence spectroscopy and nuclear magnetic resonance spectroscopy (NMR). Experimental conditions including the concentration of HP-beta-CD and media acidity were investigated in detail. The result suggested HP-beta-CD was more suitable for including CA in acidity solution. The binding contants (K) of the inclusion complexes were determined by linear regression analysis and the inclusion ratio was found to be 1:1. The water solubility of CA was increased by inclusion with HP-beta-CD according to the phase-solubility diagram. The spatial configuration of complex has been proposed based on (1)H NMR and two-dimensional (2D) NMR, the result suggested that CA was entrapped inside the hydrophobic core of HP-beta-CD with the lipophilic aromatic ring and the portion of ethylene.     

Spectral study on the inclusion complex of cryptophane-E and CHCl3

Cryptophane-E was synthesized from vanillin by a three-step method, and its absorption and fluorescence spectroscopic properties were determined. Two absorption bands at about 245–260 and 280–290 nm were observed for cryptophane-E and the fluorescence emission maxima were at 320–330 nm depending on the solvent used. The interaction of cryptophane-E with CHCl₃ was studied in detail by absorption and fluorescence spectroscopies. The results showed that cryptophane-E and CHCl₃ can easily form a stable 1:1 host–guest inclusion complex. Their binding constant (K) was determined by Benesi–Hildebrand equation and the nonlinear least squares fit method. The binding constant is largest in ethyl acetate, followed by dioxane and with acetonitrile as the smallest. In addition, the effect of guest volume on the host–guest inclusion complex was investigated. Guest molecules including CH₂Cl₂ and CCl₄ were unable to form inclusion complex with cryptophane-E because of sizes mismatching with the host cavity.     

Drug-polymer inclusion complex as a new pharmaceutical solid form

Drug-polymer crystalline inclusion complex is a new structure for the drug-polymer 2-component system, and also is a new drug solid form providing more options to optimize the drug pharmaceutical profile.     

氧化石墨烯-环糊精与金刚烷超分子包合体系的计算机模拟

理论设计了由6位单羟丙基α(β)-环糊精(Cyclodextrin,HPCD)与氧化石墨烯(GrapheneOxide,GO)共价键连接形成的复合主体化合物(GO-HPCD).结合量子化学计算(QM)和分子动力学模拟(MD),系统研究了该复合主体对金刚烷(Adamantane,AD)的超分子包合行为,并与HPCD对AD的包合进行了比较研究.对研究的结果从构型、热力学性质、径向分布函数(RadialDistributionFunction,RDF)等方面进行了全面分析.在气相条件下,B3LYP/6-31G(d,p)计算结果显示,4种主体对金刚烷的相互作用均较弱;HPαCD和GOHPαCD与金刚烷的MD模拟与QM结果一致,而HPβCD和GO-HPβCD能与金刚烷形成稳定的包合物.在水溶剂中,4种主体均能与金刚烷形成包合物,HPβCD和GO-HPβCD与金刚烷的包合物稳定性明显高于HPαCD和GO-HPαCD的包合物.氧化石墨烯片段的引入未改变环糊精与金刚烷的包合本质,但起到了辅助捕获客体分子的作用.     

The inclusion complex of piromidic acid with dimethyl-β-cyclodextrin in aqueous solution and in the solid state

Inclusion complex formation of piromidic acid (PA) with dimethyl--cyclodextrin (DM--CD) in aqueous solution and in the solid state was confirmed by the solubility method, differential scanning calorimetry (DSC) and proton nuclear magnetic resonance (¹H-NMR) spectroscopy. The apparent stability constant,K _c , of the complex was estimated to be 244 M^–1. The stoichiometry of the complex was given as the ratio 1:2 of PA to DM--CD. The dissolution rate of the PA/DM--CD complex was much greater than that of intact PA.Presented at the Fourth International Symposium on Inclusion Phenomena and the Third International Symposium on Cyclodextrins, Lancaster, U.K., 20–25 July 1986.     

Fluorimetric and molecular mechanics study of the inclusion complex of 2-quinoxalinyl-phenoxathiin with β-cyclodextrin

The complex formed by the inclusion of the polarity-sensitive fluorescent probe 2-[2′-quinoxalinyl]-phenoxathiin (QP) into β-cyclodextrin (β-CD) was investigated by steady-state fluorescence spectroscopy in order to confirm the previously stated intramolecular charge transfer nature of the first excited singlet state of QP. A decrease in the emission intensity in the presence of β-CD was observed and explained on this basis. The 1:1 stoichiometry of the inclusion complex and its association constant of 2,223 M⁻¹ were computed. The QP–β-CD complex was further studied by molecular mechanics (MM+ force field), in order to determine its structure and the type of interactions between QP and β-CD. All possible ways QP could penetrate the β-CD cavity were considered and several structures were generated and optimized. The interaction, binding (van der Waals and electrostatic contributions) and perturbation energies were also calculated. The results have showed that the β-CD cavity incorporates the central part of QP and that complexation is mainly due to van der Waals host–guest interactions.     

NMR spectroscopic study of the inclusion complex of desloratadine with β-cyclodextrin in solution

Desloratadine (DES) is an antihistamine used in the treatment of allergies and chronic urticaria. ¹H NMR spectroscopic study of varying ratios of DES and β-Cyclodextrin (β-CD) in D₂O suggests the formation of a 1:1 inclusion complex formed by the penetration of Cl-substituted aromatic ring into the β-CD cavity. The stoichiometry and binding constant of the complex were determined by Scott’s method.