Effect Of Inclusion Complex Research Articles

Characterization and evaluation of sodium alginate-based edible films by incorporation of star anise ethanol extract/hydroxypropyl-β-cyclodextrin inclusion complex

The star anise ethanol extract (SAEE)/hydroxypropyl-β-cyclodextrin (HP-β-CD) inclusion complex in sodium alginate-based composite films was evaluated for its effect on the storage of fresh-cut Chinese yam. The effect of inclusion complex on rheological, mechanical, color, optical, and thermal properties of the composite films were characterized in this study. The introduction of inclusion complex has significant effects on the mechanical, color, and rheological properties of produced films. With addition of SAEE and SAEE/HP-β-CD inclusion complex, the composite films exhibited variable degrees of antioxidant and antibacterial activities. Particular finding is that inclusion complex-based films presented higher antimicrobial activity against Rhizopus stolonifera. Meanwhile, the release study revealed that mechanical property, solution polarity, matrix structure, and light exposure affected the release efficiency of active substances from the composite films. Also, the addition of inclusion complex improved the thermal stability. Consequently, composite films incorporating the SAEE/HP-β-CD inclusion complex could serve as alternative material for coating fresh-cut Chinese yam.

The p-Anisaldehyde/β-cyclodextrin inclusion complexes as fumigation agent for control of postharvest decay and quality of strawberry

In order to evaluate the potential of developed β-cyclodextrin (β-CD)/ p -Anisaldehyde (PAA) inclusion complexes as a fumigation agent for the postharvest decay control in strawberry, both in vitro and in vivo tests were conducted. According to the colony morphology analysis on PDA media, inclusion complexes showed activity on inhibiting the mycelial growth of the fungi including Rhizopus stolonifer , Aspergillus niger and Penicillium . The effect of inclusion complexes on controlling postharvest decay in fresh strawberry was also confirmed by in vivo test, in which the inclusion complexes-treated fruit displayed significantly lower incidence and severity than control, β-CD-treated and free PAA-treated fruit. Moreover, evaluations of fruit qualities including color, weight loss, firmness and TSS, as well as the sensory indexes including appearance, color, texture and flavor were carried out in turn, showing there was no significant difference between inclusion complexes-treated fruit and the other groups. • The p -Anisaldehyde/β-CD inclusion complex was used as a fumigation agent. • The inclusion complex displayed in vitro activity against three common fungi. • The inclusion complex reduced incidence and severity of the decay in strawberry. • The inclusion complex maintained the fruit quality during storage.

On improving the spectral response of organic dyes sensitizer based on β-cyclodextrin inclusion complex

The effect of inclusion complex on the spectral response, molar extinction coefficient and the conduction mechanism of some organic dyes were studied. β- cyclodextrin inclusion complex strategy was examined on 3 different azo dyes, 2-(10-Hydroxy-anthracen-9-ylazo)-benzoic acid, 10-((4-hydroxyphenyl)diazenyl)anthracene-9-ol and N-(4,6-dimethylpyrimidin-2-yl)-4-(8-hydroxyquinolin-5-yl)diazenyl)benzenesulfonamide. The chemical structure of the obtained dyes was characterized by FTIR, 1H NMR and mass spectral studies. Inclusion complex strategy leads to get organic dyes with broader spectral response and higher molar extinction coefficient.

Effect of inclusion complexation on the photophysical behavior of diphenylamine in β-cyclodextrin medium: A study by electronic spectra

Spectral characteristics of diphenylamine (DPA) have been investigated in β-cyclodextrin (β-CDx) solution. The formation of the complex was revealed by UV, steady state and time-resolved fluorescence spectroscopy. The stoichiometry of DPA:β-CDx complex, determined using Benesi–Hildebrand equation and Job's continuous variation method is 1:1. The binding constants calculated from various methods are reported. This inclusion complex formation from DPA and β-CDx was also confirmed by the FT-IR spectral study and SEM image analysis of solid complex prepared by co-precipitation method.

Effect of inclusion complex on nitrous acid reaction with flavonoids

The kinetic of the nitrous acid reactions with quercetin and catechin has been studied using spectrophotometric method in aqueous solution. The results show that these antioxidants participate in oxidation reactions with nitrous acid which is derived from protonation of nitrite ion in mild acidic conditions. Corresponding o-quinones as relatively stable products were detected by spectrophotometric techniques. pH dependence of the reactions has been examined and the rate constants of reactions were obtained by non-linear fitting of kinetic profiles. The effect of β-cyclodextrin on the oxidation pathway was another object of this study. It is shown that β-cyclodextrin has an inhibitory effect on the oxidation reaction. The rate constants of oxidation reactions for complexed forms and their stability constants were obtained based on changes in the reaction rates as a function of β-cyclodextrin concentration.

Effect of Inclusion Complexation with Cyclodextrin on the Cloud Point of Poly(2-(dimethylamino)ethyl methacrylate) Solution

We investigated the influence of addition of cyclodextrin (CD) on the cloud point of poly(2-(dimethylamino)ethyl methacrylate) (PDMAEMA) aqueous solution. Both beta-CD and randomly methylated beta-cyclodextrin (RM-beta-CD) raised the cloud point of PDMAEMA solution; by contrast, the addition of alpha-CD or gamma-CD did not affect the cloud point of PDMAEMA solution. The inclusion complexation between side group of PDMAEMA and RM-beta-CD was confirmed by NMR experiments. The cloud point of PDMAEMA solution was raised gradually with the increase of concentration of RM-beta-CD. On the basis of inclusion complexation equilibrium, we deduced an equation, which clearly described the relationship between cloud point and concentration of RM-beta-CD. This analysis will provide an important theoretic guide for other related research. In comparison with copolymerization with another monomer, such a supramolecular approach avoids a series of synthesis and facilitates fine-tuning of cloud point.

Effect of inclusion complexation with cyclodextrins on photostability of nifedipine in solid state.

Nifedipine is a highly photosensitive drug that requires restricted protection from light during manufacturing, storage and handling of its dosage forms. Inclusion complexation of nifedipine with cyclodextrins (CDs) could be advantageous in protecting the drug against the effect of light. In this study, solid inclusion complexes of nifedipine with beta-cyclodextrin (beta-CD), hydroxypropyl-beta-cyclodextrin (HP-beta-CD) and dimethyl-beta-cyclodextrin (DM-beta-CD) were prepared using the coprecipitation method. The obtained solid inclusion complexes have been confirmed by differential scanning calorimetry (DSC), X-ray diffraction and infrared spectroscopy (IR). The IR spectra indicated partial inclusion of nifedipine molecules into CD cavities through the dihydropyridine ring. Inclusion complexation was also associated with a dramatic enhancement of drug dissolution with magnitudes depended on the type of CD. The effect of exposure to fluorescent lamp and sunlight on the photodegradation of uncomplexed and complexed nifedipine was tested. Photodegradation of nifedipine was monitored using a high performance liquid chromatographic (HPLC) assay method. Inclusion complexation of nifedipine showed to retard drug photodegradation as indicated by degradation rate constant lowering with values depended on light source and type of complexing agent. This effect was the least with beta-CD compared with that of modified beta-CD. It was also interesting to notice that inclusion complexation of nifedipine offered much higher protection against the effect of fluorescent lamp than that of sunlight. The obtained results suggests that the design of solid dosage forms of nifedipine such as a fast dissolving nifedipine tablets is possible with the advantages of low required light protection.

Effects of inclusion complexation on the transepithelial transport of a lipophilic substance in vitro.

Poor oral bioavailability of three experimental compounds, 1-III, observed in animals has been attributed to the low intrinsic solubility. To enhance their GI absorption, we attempted to increase the solubility of these compounds with hydroxypropyl beta-cyclodextrin (HPB)4 and gamma-cyclodextrin (HPG). Compound I showed an increase in solubility over 1,000-fold with 25% HPB at 25 degrees C. The association constant of the 1:1 complex between I and HPB was determined by phase-solubility analysis. Thermodynamic parameters involved were all favorable for the complexation. The large positive delta S degrees observed suggests that the complex formation is driven by a hydrophobic interaction. Apical-to-basal transport of I across the Madin Darby canine kidney (MDCK) cell monolayer was studied at 37 degrees C in the presence of HPB with or without agitation. The complex itself did not pass through the cell layer. Diffusion of the unbound I as well as the complex through the aqueous boundary layer in the apical side is rate-limiting. Regardless of hydrodynamics, decreasing HPB concentration at a given drug concentration increased the transport rate. The findings indicate that the transepithelial transport is attributed to the passive diffusion of available free drug molecules rather than the collision complex transfer at the cell surface.

Effect of 2-hydroxypropyl-β-cyclodextrin on the stability of prostaglandin E 2 in solution

The potential use of 2-hydroxypropyl-β-cyclodextrin (HP-β-CyD) in the stabilization of prostaglandin E 2 (PGE 2) was investigated. Inclusion complexation of PGE 2 with HP-β-CyD was estimated by circular dichroism spectroscopy. The effect of HP-β-CyD on the dehydration rate of PGE 2 and the isomerization rate of PGA 2 was examined by comparing the rate constant of PGE 2 alone with that of the inclusion complex of PGE 2 with HP-β-CyD in each buffered solution. The dehydration rate of PGE 2 and the isomerization rate of PGA 2 under acidic conditions were decreased by HP-β-CyD, while the rates under basic conditions were increased, probably due to positive catalytic effects on the reactions. The retardation of the dehydration and isomerization rates at low pH might be the effect of inclusion complexation with HP-β-CyD.

The Effect of Cyclodextrin Inclusion Complexation on the in Vitro Protein Binding and in Vivo Prothrombin Time of Warfarin

AbstractThat the inclusion complexation occurred in an aqueous solution was proved by solubility determination and a membrane permeation study. The effects of inclusion complexation on the protein binding and prothrombin time of warfarin were studied by the technique of ultrafiltration and prothrombin time measurements respectively. The apparent stability constant of 1:l complex was obtained from the initial portion of the straight line of phase solubility diagrams. The apparent stability constant of α or β - cyclodextrin complex is 10.29 M -1 or 148.88 M-1. The greater the stability constant of the inclusion complex the less the permeability of the warfarin. The magnitude of the stability constant of the inclusion complex also determined the protein binding and the prothrombin time of warfarin. The greater the stability constant of the inclusion complex, the lesser the protein binding and the more prolonged the prothrombin time of warfarin. β-cyclodextrin showed a significantly different behavior from α-...