Study on the Structure of Supramolecular Inclusion Complex of β-Cyclodextrin with Retinoic Acid

Inclusion compound of retinoic acid with (-cyclodextrin was prepared by coprecipitating method, the structure of resulting product was studied by elemental analysis, differential scanning caloriemetry(DSC) analysis, FT-IR spectroscopy and X-ray diffractometry, and the formed supramolecule self-assembles in aqueous solution according to molar ratio 2:1 of host-guest.

Development and evaluation of vinpocetine inclusion complex for brain targeting

The objective of this paper is to prepare vinpocetine(VIN)inclusion complex and evaluate its brain targeting effect after intranasal administration.In the present study,VIN inclusion complex was prepared in order to increase its solubility.Stability constant(Kc)was used for host selection.Factors influencing properties of the inclusion complex was investigated.Formation of the inclusion complex was identified by solubility study and DSC analysis.The brain targeting effect of the complex after intranasal administration was studied in rats.It was demonstrated that properties of the inclusion complex was mainly influenced by cyclodextrin type,organic acids type,system pH and host/guest molar ratio.Multiple component complexes can be formed by the addition of citric acid,with solubility improved for more than 23 times.Furthermore,In vivo study revealed that after intranasal administration,the absolute bioavailability of vinpocetine inclusion complex was 88%.Compared with intravenous injection,significant brain targeting effect was achieved after intranasal delivery,with brain targeting index 1.67.In conclusion,by intranasal administration of VIN inclusion complex,a fast onset of action and good brain targeting effect can be achieved.Intranasal route is a promising approach for the treatment of CNS diseases.

Strong Inclusion Complexation Using Hydroxypropyl-β-Cyclodextrin as Host Molecule

Inclusion complexes of nitro-compounds using β-cyclodextrin and hydroxypropyl-β-cyclodextrin as host molecule have been studied by cyclic voltammetric method. The inclusion constants of the corresponding complexes have been determined. Strong inclusion complexation by hydroxypropyl-β-cyclodextrin has been

Comparative Study on the Inclusion Complexation of Rutin with Cyclodextrin Supramolecules

The interaction of β-cyclodextrin(β-CD),hydroxypropyl-β-CD and -γ -CD with the drug rutin has been investigated by usingfluorimetry. The stoichiometry of the complexes and their formation constants have been estimated. The thermodynamic parameters for the formation of complexes were obtained. The complexing ability of HP-β-CD is remarkably stronger than β-CD and γ-CD.

Spectrofluorometric Study of the Inclusion Complexation of Fluorescent Whitening Agents and β-Cyclodextrins

The inclusion complexation behavior of 2,5-Bis(5-tert-butyl-benzoxazol-2yl)-thiophene (UVOB) with native β-cyclodextrin (βCD) and βCD-monochlorotriazinyl (βCD-MCT) was evaluated by fluorescence spectroscopy. The association constant (Ks), stoichiometry, , and were evaluated at 25℃ ± 0.1℃ in phosphate buffer solution (pH = 10.5, 0.1 mo•dm–3) in order to find out the complex formation ability and stability. Fluorescence enhancement for UVOB and UVBNB with both CDs has been observed as a result of the complex formation. A stoichiometry 1:1 for UVOB in both CDs was observed;a stoichiometry 3:1 for UVBNB in both CDs has been observed. The Ksvalues for UVOB were 4916 ± 137 M–1 and 655 ± 19 M–1 (acetone: water 90/10, v/v) with βCD and βCD-MCT, respectively. The value obtained indicates a spontaneous and stable complex formation, but the complex βCD-UVOB showed high Ks value as an indicative of a high concentration of complex formed. Additionally, Ks and thermodynamic parameters and were evaluated in a commercial product UVBNB (UVOB, 13%, v/v). In aqueous solution, the values obtained were 2552 ± 115 and 1787 ± 75 M–1 respectively. Complexation of UVOB with CDs is an interesting approach for utilization of UVOB in aqueous systems without the need of solvents and or surfactants used in commercial product (UVBNB).

Study of VD3-β-Clodextrin Inclusion Complex

Vitamin D is responsible for enhancing intestinal absorption of calcium, iron, magnesium, phosphate and zinc by involving in the metabolism. However, its use in additive field is limited by its low aqueous solubility and chemical stability. So trace amounts of VD3 was wrapped in β-CD molecule by the method of saturated aqueous vacuum drying, in order to improve its stability, uniformity and solubility in food and feed additive. The inclusion complex was characterized by NMR, IR techniques and compared with original VD3 in the aspect of stability and bioavailability. Results of orthogonal design experiments show that the optimum technology of inclusion is that the feed ratio of β-CD to VD3 is 15:1, being stirred for 5 hours at 80°C. Dispersion of VD3 in the inclusion complex is more uniform, while stability and absorption rate of inclusion complex are significantly higher than original VD3.

Cyclodextrin Based Host-Guest Inclusion Complex, an Approach to Enhancing the Physicochemical and Biopharmaceutical Application of Poorly Water-soluble Drugs

Host-guest inclusion complexes have been extensively studied for drug delivery applications.The host molecule,typically cyclodextrin,creates a cavity,in which the guest molecule,such as a drug,can be encapsulated.This encapsulation can protect the drug from degradation,improve its solubility and stability,and enhance its bioavailability.Moreover,host-guest inclusion complexes can facilitate targeted drug delivery by selectively releasing drugs at the site of action.Various techniques,such as covalent bonding,non-covalent interactions,and self-assembly have been used to form these complexes.Host-guest inclusion complexes have shown great potential for improving the efficacy and safety of drug delivery systems.This mini review summarizes the application and recent progress of the cyclodextrin-based host-guest inclusion complex,highlighting the enhanced physicochemical and biopharmaceutical application of pharmaceutical drugs via formulation of its inclusion complex.

Statistically designed enzymatic hydrolysis of an icariin/b-cyclodextrin inclusion complex optimized for production of icaritin

This study focuses on the preparation and enzymic hydrolysis of an icariin/bcyclodextrin inclusion complex to efficiently generate icaritin.The physical characteristics of the inclusion complex were evaluated by differential scanning calorimetry(DSC).Enzymatic hydrolysis was optimized for the conversion of icariin/b-cyclodextrin complex to icaritin by Box–Behnken statistical design.The inclusion complex formulation increased the solubility of icariin approximately 17-fold,from 29.2 to 513.5 mg/mL at 60℃.The optimum conditions were predicted by Box–Behnken statistical design as follows:60℃,pH 7.0,the ratio of enzyme/substrate(1:1.1)and reaction time 7 h.Under the optimal conditions the conversion of icariin was 97.91%and the reaction time was decreased by 68%compared with that without b-CD inclusion.Product analysis by melting point,ESI-MS,UV,IR,1H NMR and 13C NMR confirmed the authenticity of icaritin with a purity of 99.3%and a yield of 473 mg of icaritin from 1.1 g icariin.

Using the Box-Behnken Response Surface Method to Optimize the Preparation and Characterization of Lavender and Fennel Volatile oilβ-cyclodextrin Form Inclusion Complex

Objective:The objective of this study is to study the best inclusion technology of Lavender-and fennel-mixed volatile oil by beta?cyclodextrin(β-CD) and characterize the final product thereafter.Methods:Using the saturated water solution method,the volatile β-CD inclusion complex was produced.The effect of volatile oil weight ratio,inclusion temperature and inclusion time on the inclusive quality was studied by measuring the yield of inclusion and inclusion rate of volatile oil as evaluation indexes.The preparation method of inclusion complex was then optimized by the Box-Behnken response surface method.The inclusion complex was characterized by ultraviolet spectrophotometry,thin-layer chromatography,thermogravimetry and differential thermal analysis,and the microscopic imaging method.Results:The optimized conditions were the weight ratio of β-CD to volatile oil was 8.13:1(g/ml).The inclusion temperature was 44°C.The inclusion time was 1 h.Conclusion:We were able to produce an inclusion complex with high inclusion rate of volatile oil and high yield of inclusion using the preparation method mentioned above.Furthermore,the method can also improve the stability of volatile oil in abnormal savda munziq.This study can provide a good reference for the development of new preparations.

Intranasal temperature-sensitive hydrogels of cannabidiol inclusion complex for the treatment of post-traumatic stress disorder

Post-traumatic stress disorder(PTSD)is a psychiatric disease that seriously affects brain function.Currently,selective serotonin reuptake inhibitors(SSRIs)are used to treat PTSD clinically but have decreased efficiency and increased side effects.In this study,nasal cannabidiol inclusion complex temperature-sensitive hydrogels(CBD TSGs)were prepared and evaluated to treat PTSD.Mice model of PTSD was established with conditional fear box.CBD TSGs could significantly improve the spontaneous behavior,exploratory spirit and alleviate tension in open field box,relieve anxiety and tension in elevated plus maze,and reduce the freezing time.Hematoxylin and eosin and c-FOS immunohistochemistry slides showed that the main injured brain areas in PTSD were the prefrontal cortex,amygdala,and hippocampus CA1.CBD TSGs could reduce the level of tumor necrosis factor-a caused by PTSD.Western blot analysis showed that CBD TSGs increased the expression of the 5-HT1 A receptor.Intranasal administration of CBD TSGs was more efficient and had more obvious brain targeting effects than oral administration,as evidenced by the pharmacokinetics and brain tissue distribution of CBD TSGs.Overall,nasal CBD TSGs are safe and effective and have controlled release.There are a novel promising option for the clinical treatment of PTSD.

Gallic Acid/2-Hydroxypropyl-β-cyclodextrin Inclusion Complexes Electrospun Nanofibrous Webs:Fast Dissolution,Improved Aqueous Solubility and Antioxidant Property of Gallic Acid

Gallic acid(GA)is a kind of natural polyphenolic compound,but its low aqueous solubility restricts its application in the fields of food and medicine.Cyclodextrin can form inclusion complexes with guest molecules(e.g.,essential oils,food supplements)through cavities with special properties to improve aqueous solubility,thermal stability,and bioavailability of guest molecules.In this research,gallic acid/2-hydroxypropyl-β-cyclodextrin inclusion complexes(GA/2-HP-β-CD/ICs)were formed in a highly concentrated solution of 2-HP-β-CD.Bead-free and uniform nanofibrous webs(GA/2-HP-β-CD/IC-NWs)were produced successfully by electrospun GA/HP-β-CD/IC aqueous solution.The initial molar ratio(GA:2-HP-β-CD=1:1)of GA/2-HP-β-CD/IC in the solutions was largely maintained in GA/2-HP-β-CD/IC-NW.The aqueous solubility of GA was enhanced and GA/2-HP-β-CD/IC-NW has displayed fast dissolution property.Furthermore,in comparison with GA powder,GA/2-HP-β-CD/IC-NW demonstrated improved antioxidant capacity.The results suggested that GA/2-HP-β-CD/IC-NW have broad application prospects as orally fast dissolution systems for food supplements.

Water-soluble crosslinked β-cyclodextrin polymer inclusion complexes with C60

At present, using cyclodextrins or cyclodextrin derivatives with suitable internal annular dimension to embed C60 so as to form inclusion complexes has been one of the main ways to improve C60＇s water-solubility. In three kinds of cyclodextrins (α-, β-, γ-CD), only γ-CD has cavity large enough to include C60 whereas α-, and β-CD have not. In the case of DMβCD, the "out-stretching" methyl groups enlarge the cavity so that it can include C60. Starting from the same thought, we use epichlorohydrin crosslinked

Analytical and technological aspects of amylose inclusion complexes for potential applications in functional foods

The linear component of starch,amylose,has the ability to interact with hydrophobic molecules forming inclusion complexes(ICs).These structures have gained a particular interest for potential food applications,either as dietary fiber or as delivery systems of bioactive compounds.In the second case,the complexation of sensitive molecules is directed to protect them from processing,storage and stomach conditions and to guarantee a sustained release in the gastrointestinal tract.The present review covers the analytical and technological aspects of inclusion complexes,with focus on their potential application in the development of functional foods.It was addressed by first explaining the methodologies used for the analytical assessment of their structural,thermal,and functional properties,followed by the study of the functionality of ICs as carrier agents of different bioactive compounds and food ingredients,including alpha-lipoic acid,α-linolenic and linoleic fatty acids,conjugated linoleic acid,ascorbyl palmitate,phenolic compounds,and flavors.It also covers the application of ICs in food products and the analysis of the potential industrial scalability of the formation process.The analytical methodologies allowed a complete characterization of the ICs.These structures have shown suitable functional properties as delivery systems of the bioactive compounds and flavors covered in this review.The incorporation of ICs in food has led to the development of products with improved nutritional and/or functional value.The successful formation of complexes using methods suitable for an industrial scale represents promising preliminary results to achieve the scalability of the ICs production in the near future.

Complexation with pre-formed“empty”V-type starch for encapsulation of aroma compounds

Aroma compounds are low-molecular-weight organic volatile molecules and are broadly utilized in the food industry.However,due to their high volatility and evaporative losses during processing and storage,the stabilization of these volatile ingredients using encapsulation is a commonly investigated practice.Complexation of aroma compounds using starch inclusion complex could be a potential approach due to the hydrophobicity of the left-handed single helical structure.In the present study,we used starch of three different V-type structures,namely V,V,and V,to encapsulate six different aroma compounds,including1-decanol(DN),cis-3-hexen-1-ol(HN),4-allylanisole(AN),γ-decalactone(DA),trans-cinnamaldehyde(CA),and citral(CT).The formed inclusion complexes samples were characterized using complementary techniques,including X-ray diffraction(XRD)and differential scanning calorimetry(DSC).The results showed that upon complexation with aroma compounds,all V-subtypes retained their original crystalline structures.However,different trends of crystallinity were observed for each type of the prepared inclusion complexes.Additionally,among three V-type starches,V-type starch formed inclusion complexes with aroma compounds most efficiently and promoted the formation of FormⅡcomplex.This study suggested that the structure of aroma compounds and the type of V starch could both affect the complexation properties.

A Theoretical Study on the Stereoisomerism in the Complex of Cucurbit[8]uril with 2,6-Bis(4,5-dihydro-1H-imidazol-2-yl)naphthalene

Semiempirical PM3 and density function theory B3LYP/3-21g* calculations in vacuum and in water indicated that the "syn" orientation was preferred in the 1:2 complex of cucurbit[8]uril with protonated 2, 6-bis(4, 5-dihydro-1H-imidazol-2-yl)naphthalene. The (-( stacking interaction between the two substrate molecules was proposed as the physical origin of such a behavior.

Water-Based Environmentally Friendly Pesticide Formulations Based on Cyclodextrin/Pesticide Loading System

Difenoconazole(DIF)is a representative variety of broad-spectrum triazole fungicides and liposoluble pesticides.However,the water solubility of DIF is so poor that its application is limited in plant protection.In addition,the conventional formulations of DIF always contain abundant organic solvents,which may cause pollution of the environment.In this study,two DIF/cyclodextrins(CDs)inclusion complexes(ICs)were successfully prepared,which were DIF/β-CD IC and DIF/hydroxypropyl-β-CD IC(DIF/HP-β-CD IC).The effect of cyclodextrins on the water solubility and the antifungal effect of liposoluble DIF pesticide were investigated.According to the phase solubility test,the molar ratio and apparent stability constant of ICs were obtained.Fourier transform infrared spectroscopy,thermal gravity analysis,X-ray diffraction and scanning electron microscopy were used systematically to characterize the formation and characteristics of ICs.The results noted that DIF successfully entered the cavities of two CDs.In addition,the antifungal effect test proved the better performance of DIF/HP-β-CD IC,which exceeded that of DIF emulsifiable concentrate.Therefore,our study provides informative direction for the intelligent use of liposoluble pesticides with cyclodextrins to develop water-based environmentally friendly formulations.