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1.
Takeshi Furuta Youko Kusuya Tze-loon Neoh Lars Rehmann Sun-hwa Beak Hidefumi Yoshii 《Journal of inclusion phenomena and macrocyclic chemistry》2006,56(1-2):107-111
The potential for surface modification of paper by modified cyclodextrins was demonstrated by the model system of Japanese washi paper and monochlorotriazinyl-β-cyclodextrin (MCT-β-CD). MCT-β-CD was covalently bonded to the paper. The optimal bonded reaction conditions were found to be 10 min at 150 °C with a moisture content of less than 2.5 (g water/g dry paper). The bounded MCT-β-CD on the paper was able to include and release hinokitiol representing the group of antibacterial agents. The maximum molar inclusion ratio of hinokitiol in the immobilized MCT-β-CD was around 0.8. The release rates of hinokitiol, included in the fixed MCT-β-CD, were monitored at 50 °C for different relative humidities. The release rate was strongly influenced by the relative humidity. These results demonstrate that the antibacterial agent can be included and released from MCT-β-CD fixed on the paper. The antibacterial activity of the fixed hinokitiol against airborne microorganisms was demonstrated. 相似文献
2.
R. Patel D. Bhimani J. Patel D. Patel 《Journal of inclusion phenomena and macrocyclic chemistry》2008,60(3-4):241-251
The objectives of this research were to prepare and characterize inclusion complex of Ezetimibe (EZE) with cyclodextrins (β-cyclodextrin
(β-CD) and hydroxypropyl-β-cyclodextrin (HPβ-CD)) and to study the effect of complexation on the dissolution rate of EZE,
a water insoluble drug. Phase solubility curve was classified as A
P
-type for both cyclodextrins, indicating the 2:1 stoichiometric ratio for β-CD–EZE and HPβ-CD – EZE inclusion complexes. The
inclusion complexes in the molar ratio of 2:1 (β-CD–EZE and HPβ-CD–EZE) were prepared by various methods such as kneading,
coevaporation and physical mixing. The molecular behaviors of drug in all samples were characterized by fourier-transform
infrared (FTIR) spectroscopy, differential scanning calorimetry (DSC) and powder X-ray diffraction (PXRD) studies. The results
of these studies indicated that complex prepared by kneading and coevaporation methods showed inclusion of the EZE molecule
into the cyclodextrins cavities. The highest improvement in in-vitro dissolution profiles was observed in complex prepared
with hydroxypropyl-β-cyclodextrin using co-evaporation method. Mean dissolution time and similarity factor indicated significant
difference between the release profiles of EZE from complexes and physical mixtures and from pure EZE. 相似文献
3.
Erem Bilensoy Lale Doğan Murat Şen Atilla Hıncal 《Journal of inclusion phenomena and macrocyclic chemistry》2007,57(1-4):651-655
Inclusion complexes of the poorly-soluble antiestrogen drug tamoxifen citrate (TMX) were prepared with β-cyclodextrin (β-CD)
and 2,3-di-O-hexanoyl-β-cyclodextrin (β-CDC6) being natural and amphiphilic cyclodextrins, respectively using the co-lyophilization technique.
Complexation occurred in aqueous medium for natural cyclodextrin β-CD and a medium of water:ethanol mixture for the amphiphilic
cyclodextrin β-CDC6. The complexes were characterized using analytical techniques including Differential Scanning Calorimetry
(DSC), Fourier Transform Infrared spectroscopy (FTIR) and proton Nuclear Magnetic Resonance Spectrometry (1H NMR). Anticancer efficacies of the complexes were determined against MCF-7 human breast carcinoma cell line with MTT assay.
It was found that tamoxifen citrate can be incorporated in the cavity for β-CD and both in the cavity and the aliphatic chains
for β-CDC6. The latter having two hydrophobic sites for inclusion of water-insoluble drug exhibited significantly higher anticancer
efficacy accordingly. 相似文献
4.
Andrés G. León Ana I. Olives M. Antonia Martín Benito del Castillo 《Journal of inclusion phenomena and macrocyclic chemistry》2007,57(1-4):577-583
The use of cyclodextrins (CDs) in HPLC as mobile phase additives provides a flexible alternative for the separation of chemically
related compounds because these separations can be performed on conventional columns and are economically advantageous over
the use of chiral stationary phases. The present paper describes the influence of the presence of β-cyclodextrin (β-CD) and
2-hydroxypropyl-β-cyclodextrin (HPβ-CD) on the separation of the β-carboline alkaloids norharmane, harmane and harmine. The
nature of the stationary phase (reverse phases C1 and C18) affects the chromatographic separations and also the stability of the inclusion complexes that are developed. The changes
in the proportion of the organic solvents at constant concentration of CDs (3 mM for β-CD and 15 mM for HPβ-CD) modify the
retention factors (k′) for all alkaloids studied. The nature of the organic solvent in the mobile phase also changes the chromatographic parameters.
The logarithm of the capacity factor (k′) is linearly increased with the proportion of water in the hydro-organic mobile phase (ethanolic or methanolic) but the
slopes obtained vary depending on the CD added to the mobile phase. The role of competitive equilibria, i.e., chromatographic
distribution and inclusion complexes formation is discussed.
This paper was presented at XIIIth International Cyclodextrin Symposium. Torino, Italy, May, 14–17, 2006 相似文献
5.
H. Krajian N. Mofaddel D. Villemin P. L. Desbène 《Analytical and bioanalytical chemistry》2009,394(8):2193-2201
Enantioseparation of 6,6′-dibromo-1,1′-binaphthyl-2,2′-diol (DBBD) by cyclodextrin-modified capillary zone electrophoresis
(CD-CZE) was studied using the three native α, β, and γ cyclodextrins, the three hydroxypropylated cyclodextrins (2-hydroxypropyl-α,
β, and γ), heptakis-2,6-di-O-methyl-β-CD (DM-β-CD), and heptakis-2,3,6-tri-O-methyl-β-cyclodextrin (TM-β-CD). First, the acidity constants of DBBD were determined using capillary electrophoresis, before
performing enantioseparation. The influence of the concentrations of the studied cyclodextrins on the enantioseparation was
explored and the experimental optimal concentrations were determined and compared to the theoretical optimal concentrations.
Moreover, the apparent complexation constants between each studied cyclodextrin and the two DBBD enantiomers were evaluated
using a non-linear curve fitting method and three linear plotting methods (x-reciprocal, y-reciprocal and double reciprocal). For TM-β-CD, the order of migration of the enantiomers of DBBD reversed as a function
of TM-β-CD concentration. The influence of the nature of methylated cyclodextrin derivatives (methyl-β-CD (M-β-CD) and DM-β-CD)
was then studied. Inversion of the order of migration of the enantiomers of DBBD was observed for DM-β-CD, whereas the S enantiomer of DBBD always migrated first for M-β-CD. 相似文献
6.
Silvia Simeoni Santo Scalia Rosanna Tursilli Heather Benson 《Journal of inclusion phenomena and macrocyclic chemistry》2006,54(3-4):275-282
The objective of this study was to investigate the influence of cyclodextrins on the cutaneous availability of the sunscreen oxybenzone. The interaction between oxybenzone and hydrophilic α-, β- and γ-cyclodextrin derivatives was studied in water by phase-solubility analysis. Among the available cyclodextrins, hydroxypropyl-β-cyclodextrin (HP-β-CD) and especially sulfobutylether-β-cyclodextrin (SBE-β-CD) had the greatest solubilizing activity. Ethanol–water solutions containing oxybenzone free or complexed with HP-β-CD or SBE-β-CD were applied to human skin in Franz diffusion cells and the amount of sunscreen permeated into the different cutaneous compartments was determined by HPLC. As much as 20.5% of the oxybenzone applied dose diffused within the skin tissue after 6 h application. Between 39.4% and 54.9% of the penetrated UV filter was localized in the stratum corneum, with no significant difference between uncomplexed oxybenzone or its complex with HP-β-CD. Conversely, the amount retained in the stratum corneum was markedly decreased (ca. 50%) by complexation with SBE-β-CD. Considerable quantities of oxybenzone accumulated into the viable epidermis (5.7% of the applied dose) and dermis (6.2% of the applied dose) from the preparation containing the free UV filter. The sunscreen penetration to the deeper living layers of the skin was remarkably lower (1.0% and 2.0% of applied dose for epidermis and dermis, respectively) upon application of the sunscreen complexed with SBE-β-CD, whereas HP-β-CD had no effect. In addition, photostability experiments demonstrated that SBE-β-CD complexation did not alter the sunscreen photochemical properties. 相似文献
7.
Tardioli Paulo W. Zanin Gisella M. de Moraes Flávio F. 《Applied biochemistry and biotechnology》2000,84(1-9):1003-1019
Cyclodextrin-glycosyl-transferase (EC2.4.1.19), produced by Wacker (Munich, Germany), was purified by biospecific affinity
chromatography with β-cyclodextrin (β-CD) as ligand, and immobilized into controlled pore silica particles (0.42 mm). This
immobilized enzyme (IE) had 4.7 mg of protein/g of support and a specific activity of 8.6 μmol of β-CD/(min·gIF) at 50°C, pH 8.0. It was used in a fluidized-bed reactor (FBR) at the same conditions for producing cyclodextrins (CDs) with
10% (w/v) maltodextrin solution as substrate. Bed expansion was modeled by the Richardson and Zaki equation, giving a good
fit in two distin ctranges of bed porosities. The minimum fluidization velocity was 0.045 cm/s, the bed expansion coefficient
was 3.98, and the particle terminal velocity was 2.4 cm/s. The FBR achieved high productivity, reaching in only 4 min of residence
time the same amount of CDs normally achieved in a batch reactor with free enzyme after 24h of reaction, namely, 10.4 mM β-CD
and 2.3 mM γ-CD. 相似文献
8.
Summary Ultrahigh pressure liquid chromatography was demonstrated for fast and efficient chiral separations. Capillary columns approximately
13–24 cm in length packed with nonporous 1.0μm C6-modified silical particles were used. β-Cyclodextrin (β-CD) and 2-hydroxypropyl-β-cyclodextrin (HP-β-CD) were added to the
mobile phase as modifiers to produce transient diastereomeric complexes with the analytes. Pressures up to ≈42,000 psi were
applied, and efficiencies in excess of 200,000 plates m−1 were obtained for separations that were accomplished in less than 2 minutes. 相似文献
9.
Binary Systems of Nifedipine And Various Cyclodextrins in The Solid State. Thermal,FTIR, XRD studies
Brown M. E. Glass B. D. Worthington M. S. 《Journal of Thermal Analysis and Calorimetry》2002,68(2):631-646
Nifedipine complexes with β-cyclodextrin (β-CD), γ-cyclodextrin (γ-CD), 2-hydroxypropyl-β-cyclodextrin (2HP-β-CD), randomly
methylated-β-cyclodextrin (RM-β-CD) and heptakis(2,6-O-dimethyl)-β-cyclodextrin (DM-β-CD) have been prepared by both kneading and heating methods and their behaviour studied by
differential scanning calorimetry (DSC), diffuse reflectance mid-infrared spectroscopy (FTIR) and X-ray diffractometry (XRD).
DSC revealed the nifedipine melting endotherm with onset at approximately 171°C for the kneaded mixtures with β-CD, γ-CD and
2HP-β-CD, thus confirming the presence of nifedipine in the crystalline state, while some decrease in crystallinity was observed
in the DM-β-CD kneaded mixture. With RM-β-CD, however, broadening and shifting of the nifedipine endotherm and reduction in
its intensity suggested that the kneading could have produced an amorphous inclusion complex. These differing extents of interaction
of nifedipine with the cyclodextrins were confirmed by FTIR and XRD studies.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
10.
E. Fontananova G. Di Profio E. Curcio L. Giorno E. Drioli 《Journal of inclusion phenomena and macrocyclic chemistry》2007,57(1-4):537-543
In this paper a new method for the functionalization of porous membranes with β-CD is reported. Porous polypropylene (PP)
hollow fibres have been impregnated with a mixture composed by a partially cross-linked polydimethylsiloxane (PDMS) and β-cyclodextrin
(β-CD). The prepolymerization of the PDMS components was necessary to avoid their inclusion in the β-CD cavity. The firm heterogenization
of the β-CD was obtained by in situ cross-linking of the PDMS/β-CD network in the porous membranes.
The presence of the PDMS/β-CD network in the membranes was confirmed by FT-IR-ATR (on the outer and inner surfaces) and EDX
analyses (on the cross-section).The effect of the impregnation times on membrane morphology, loading and porosity has been
investigated.
The binding capacity of the heterogenized β-CDs has been tested using the phenolphthalein as guest molecule. 相似文献
11.
Matioli Graciette Zanin Gisella M. Gljimarães Manoel F. De moraes Flávio f. 《Applied biochemistry and biotechnology》1998,(1):267-275
Alkalophylic bacilli that produce cyclodextringlycosyltransferase (CGTase) were isolated from Brazilian soil, with a scheme
of two plating steps. In the first step, the bacterial isolate forms a halo in the cultivation medium that contains γ-cyclodextrin
(CD) complexing dyes. The CGTase of an isolate was purified 157-fold by biospecific affinity chromatography, with β-CD showing
a mol wt of 77,580 Daltons. It produces a γ- to β-CD ratio of 0.156 and a small amount of α-CD, using maltodextrin 10% as
substrate, at 50°C, pH 8.0 and 22 h reaction time, reaching 21.4% conversion of the substrate to cyclodextrins. In the second
screening step, the isolates chosen give larger halos with β-CD complexing dyes, and smaller halos with β-CD complexing dyes,
leading to a 30% improvement in γ-CD selectivity, although at lower total yield for cyclodextrins (11.5%). 相似文献
12.
A novel determination method of electroinactive molecules by means of electrochemical technique is presented. A new self-assembled monolayer containing cyclodextrin (CD) is prepared with mono(6-o-p-tolylsulfonyl)-β-cyclodextrin. Although this derivatization process leads to a β-CD coverage of 10% of a full monolayer, this layer shows an effective host-guest response to ferrocene. The interfacial ferrocene complexation gives a response similar to that expected for a Langmuir adsorption isotherm yielding a stability constant of 4.2 ×104 mol-1· L and a maximum ferrocene coverage of 8.6×10-12 mol/cm2. The redox peak currents of the surface-confined ferrocene decrease upon addition of competing β-CD guest species to the solution, such as m-toluic acid (mTA) and sodium dodecyl sulfonate (SDS). This principle has been used for the determination of the electroinactive molecules, mTA and SDS in the concentration ranges of 0.8-2.7 μmol/L and 5-100 nmol/L, respectively. 相似文献
13.
Le Xin Song Chuan Feng Teng Peng Xu Hai Ming Wang Zi Qiang Zhang Qing Qing Liu 《Journal of inclusion phenomena and macrocyclic chemistry》2008,60(3-4):223-233
The present work revealed there was a conceptual difference in the thermal decomposition behaviors between the complexed β-cyclodextrin
(CD) in an inclusion system and the β-CD complex of guest. The thermal decomposition behaviors of the solid inclusion complexes
of β-CD with ethylenediamine (Eda), diethylenetriamine (Dta) and triethylamine (Tea) were investigated using nonisothermal
thermogravimetry (TG) analysis based on weight loss as a function of temperature. In view of TG profiles, a consecutive mechanism
describing the formation and thermal decomposition of the three solid supermolecules of β-CD was presented. Heating rate has
very different effects on the thermal decomposition behaviors of these complexes. The faster the heating rate is, the higher
the melting-decomposition point of the complexed β-CD in an inclusion system is, and on the whole the bigger the rate constant
(k) of the thermal decomposition reaction of the complexed β-CD is. The thermal decomposition process of the complexed β-CD
for each inclusion system is determined to be simple first-order reaction using Ozawa method. The apparent activation energies
(E
a) and frequency factors (A) of the thermal decomposition reactions of the complexed β-CD molecules have been also calculated. It is found that when
the decomposition reaction of the complexed β-CD encountered a large value of E
a, such as that in Dta–β-CD system, an apparent compensation effect of A on E
a can provide enough energy to conquer the reaction barrier in prompting the k value of thermal decomposition reaction of the complexed β-CD according to Arrhenius equation. 相似文献
14.
Sulphamethizole-Cyclodextrin-Hydroxy Propylmethyl Cellulose Multicomponent Complexes 总被引:4,自引:0,他引:4
Pose-Vilarnovo B. Rodríguez-Tenreiro Sánchez X Pérez-Marcos M. B. Torres-Labandeira J. J. 《Journal of Thermal Analysis and Calorimetry》2002,68(2):657-667
The effect of cyclodextrin complexation of sulphamethizole (SM) was studied. Two systems were prepared with two cyclodextrin
derivatives, β-cyclodextrin (BCD) and hydroxypropyl-β-cyclodextrin (HPBCD): binary complexes and multicomponent systems (cyclodextrins
and a hydroxylpropylmethyl cellulose K4M). Inclusion complexes were prepared by freeze-drying and characterized by thermal
analysis (DSC) and X-ray diffractometry. The presence of the polymer in the solution increases the effect of cyclodextrins
– specially BCD – on the solubility of SM. In solid state, binary inclusion complexes enhance the dissolution behaviour of
SM but, from the multi-component complexes, the polymer controls the release of the drug.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
15.
Mame Diabou Gaye Seye C. Parrain J.J. Aaron N. Motohashi 《Journal of inclusion phenomena and macrocyclic chemistry》2006,55(3-4):271-277
The electronic absorption and fluorescence spectral properties of 11-methyl-12H-benzo[a]phenothiazine (11-MeBPHT) were investigated in various media (water, ethanol, β-cyclodextrin (β-CD) and 2-hydroxypropyl-β-cyclodextrin (HP-β-CD) aqueous solutions). Fluorescence quantum yields were respectively about 20 and 2 times larger in HP-β-CD and β-CD than in water. The formation of a 1:1 stoichiometry inclusion complex between 11-MeBPHT and HP-β-CD (association constant K
f=118±3 M−1 at 20 °C) was studied in aqueous medium by fluorescence spectroscopy. Analytical figures of merit were satisfactory for 11-MeBPHT with linear dynamic ranges over at least two orders of magnitude and limits of detection (LODs) between 0.2 and 1 ng/ml according to the medium. An analytical application to the determination of 11-MeBPHT in human urine samples by the standard addition procedure led to satisfactory recovery percentages (91–108%). 相似文献
16.
G S Yang D M Chen Y Yang B Tang J J Gao H Y Aboul-Enein B Koppenhoefer 《Chromatographia》2005,62(7-8):441-445
The enantiomeric separation of 37 clinically used racemic basic drugs among 50 drugs was achieved using sulfated β-cyclodextrin
(S-β-CD) as chiral selector at pH2.5 and in the reversed polarity mode. The results obtained in this study were different
from the one obtained using neutral β-CD and its derivatives as chiral selectors. Using S-β-CD as chiral selector did not
require the presence of the substructure 4H to achieve chiral separation as observed with β-Cyclodextrin (β-CD) and its derivatives
since among the 37 separated drugs only 7 possess the 4H substructure. The chiral discrimination depends on the appropriate
interaction between the analyte and the sulfated β-cyclodextrin. 相似文献
17.
Microencapsulation of cinnamon leaf (Cinnamomum zeylanicum) and garlic (Allium sativum) oils in β-cyclodextrin 总被引:1,自引:0,他引:1
J. Fernando Ayala-Zavala Herlinda Soto-Valdez Alberto González-León Emilio Álvarez-Parrilla Olga Martín-Belloso Gustavo A. González-Aguilar 《Journal of inclusion phenomena and macrocyclic chemistry》2008,60(3-4):359-368
Cinnamon leaf (CLO) and garlic oils (GO) are good antimicrobials, however, their volatility complicates their application
as food preservatives. Hence, microencapsulation of CLO and GO with β-cyclodextrin (β-CD) was studied at 4:96, 8:92, 12:88,
and 16:84 (oil:β-CD) percent weight ratios. Microcapsule characterization included gas chromatography analysis, moisture sorption–desorption
isotherms, infrared spectroscopy (IR), and antifungal activity against Alternaria alternata. Major oil constituents were eugenol for CLO and allyl disulfide for GO. The 16:84 ratio (CLO:β-CD) showed the highest eugenol
content; the allyl disulfide content was higher, but not significantly different (P > 0.05) for the 12:88 and 16:84 ratios. Microcapsules showed lower moisture sorption than β-CD, although during water desorption
there were no difference between them. Hydrogen bonds were detected between oil constituents and β-CD by IR spectroscopy.
CLO:β-CD and GO:β-CD microcapsules displayed good antifungal activity against Alternaria alternata. Therefore, CLO and GO microcapsules can have important applications in the food industry as stable natural antimicrobial
compound systems. 相似文献
18.
A. Anton Smith K. Kannan R. Manavalan N. Rajendiran 《Journal of inclusion phenomena and macrocyclic chemistry》2007,58(1-2):161-167
Absorption and fluorescence spectra of bicalutamide (BCA) in different solvents and aqueous β-cyclodextrin (β-CD) solutions
are reported. The solid inclusion complex of BCA with β-CD is prepared and investigated by FT-IR, 1H NMR, differential scanning colorimetry (DSC) and scanning electron microscopy (SEM). The Stokes shift of BCA is correlated
with various solvent polarity scales like E
T(30), BK and f(D,n). β-CD studies show that (i) the absorption and emission maxima of BCA are shifted to red, (ii) the absorbance is slightly
decreased whereas emission intensity is increased largely with an increasing β-CD concentration, (iii) BCA forms 1:1 inclusion
complex with β-CD and (iv) intramolecular charge transfer (ICT) emission is present in the excited state. 相似文献
19.
Xiao-Xiang Li Jun-Wen Wang Yu-Jing Guo Ling-Hong Kong Jing-Hao Pan 《Journal of inclusion phenomena and macrocyclic chemistry》2007,58(3-4):307-315
In phosphate buffer solution of pH5.4, the interaction of meso-tetrakis(2-thienyl)porphyrin(H2TTP) and Cu-meso-tetrakis(2-thienyl)porphyrin(Cu-TTP) with α-cyclodextrin(α-CD), β-CD, γ-CD, heptakis(2,3,6-tri-O-methyl)-β-CD(TM-β-CD)
has been studied by means of UV-vis, fluorescence and 1HNMR spectroscopy, respectively. The H2TTP and Cu-TTP can form 1:2 inclusion complexes with TM-β-CD and 1:1 inclusion complexes with the other three cyclodextrins.
In this paper, the inclusion constants (K) of H2TTP and Cu-TTP for the formation of the inclusion complexes have been estimated from the changes of absorbance and fluorescence
intensity in phosphate buffer solution. The inclusive capabilities of different kinds of cyclodextrins are compared. The result
shows that the inclusion ability of α-CD with H2TTP and Cu-TTP is the strongest among the three native CDs. The inclusion ability of modified β-CD with H2TTP and Cu-TTP is stronger, compared to the native β-CD, which indicates that the capacity matching plays a crucial role in
the inclusion procedure except for the hydrophobic effect. In addition 1HNMR spectra supports the inclusion conformation of the TM-β-CD-Cu-TTP inclusion complex, indicating the interaction mechanism
of inclusion processes. 相似文献
20.
R. Verrone L. Catucci P. Cosma P. Fini A. Agostiano V. Lippolis M. Pascale 《Journal of inclusion phenomena and macrocyclic chemistry》2007,57(1-4):475-479
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 β-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/β-CD inclusion complexes have been determined by applying modified Benesi-Hildebrand equation.
A 1:1 stoichiometry of OTA/β-CD complexes has been observed at all tested pHs. 相似文献