Inclusion Compound Formation with a New Columnar Cyclodextrin Host

Rusa, Cristian C.; Bullions, Todd A.; Fox, Justin D.; Porbeni, Francis E.; Wang, Xin; Tonelli, Alan E.

doi:10.1021/la0262452

Cited by 173 publications

(209 citation statements)

References 31 publications

(48 reference statements)

Supporting

Mentioning

186

Contrasting

Order By: Relevance

“…In the case of vanillin/γ-CD IC obtained by coprecipitation technique, the XRD pattern has a major peak at 2θ = 7.5°along with minor diffractions at 2θ = 14.2°, 15°, 16°, 16.8°, and 22°, confirming the tetragonal channel-type packing of γ-CD. 26,27 The XRD pattern of vanillin/γ-CD IC obtained by freeze-drying is similar to that of the vanillin/γ-CD IC obtained by coprecipitation method; yet, the peaks are relatively broad, indicating that the material was partially amorphous. In addition, the peak at 2θ = 6.2°corresponding to channel structure with hexagonal packing was also observed.…”

Section: Journal Of Agricultural and Food Chemistrysupporting

confidence: 52%

See 1 more Smart Citation

Solid Inclusion Complexes of Vanillin with Cyclodextrins: Their Formation, Characterization, and High-Temperature Stability

Kayacı

Uyar

2011

J. Agric. Food Chem.

128

View full text Add to dashboard Cite

This study reports the formation of solid vanillin/cyclodextrin inclusion complexes (vanillin/CD ICs) with the aim to enhance the thermal stability and sustained release of vanillin by inclusion complexation. The solid vanillin/CD ICs with three types of CDs (α-CD, β-CD, and γ-CD) were prepared using the freeze-drying method; in addition, a coprecipitation method was also used in the case of γ-CD. The presence of vanillin in CD ICs was confirmed by FTIR and 1 H NMR studies. Moreover, 1 H NMR study elucidated that the complexation stoichiometry for both vanillin/β-CD IC and vanillin/γ-CD IC was a 1:1 molar ratio, whereas it was 0.625:1 for vanillin/α-CD IC. XRD studies have shown channel-type arrangement for CD molecules, and no diffraction peak for free vanillin was observed for vanillin/β-CD IC and vanillin/γ-CD IC, indicating that complete inclusion complexation was successfully achieved for these CD ICs. In the case of vanillin/α-CD IC, the sample was mostly amorphous and some uncomplexed vanillin was present, suggesting that α-CD was not very effective for complexation with vanillin compared to β-CD and γ-CD. Furthermore, DSC studies for vanillin/β-CD IC and vanillin/γ-CD IC have shown no melting point for vanillin, elucidating the true complex formation, whereas a melting point for vanillin was recorded for vanillin/α-CD IC, confirming the presence of some uncomplexed vanillin in this sample. TGA thermograms indicated that thermal evaporation/degradation of vanillin occurred over a much higher temperature range (150À300°C) for vanillin/CD ICs samples when compared to pure vanillin (80À200°C) or vanillin/CD physical mixtures, signifying that the thermal stability of vanillin was increased due to the inclusion complexation with CDs. Moreover, headspace GC-MS analyses indicated that the release of vanillin was sustained at higher temperatures in the case of vanillin/CD ICs due to the inclusion complexation when compared to vanillin/CD physical mixtures. The amount of vanillin released with increasing temperature was lowest for vanillin/γ-CD IC and highest for vanillin/α-CD IC, suggesting that the strength of interaction between vanillin and the CD cavity was in the order γ-CD > β-CD > α-CD for solid vanillin/CD ICs.

show abstract

Section: Journal Of Agricultural and Food Chemistrysupporting

confidence: 52%

“…The α-CD having channel-type structure has two prominent peaks centered at 2θ = 13°and 2θ = 20°. 27 As mentioned above, vanillin has a major diffraction peak at 2θ = 13° (Figure 4b). The overlapping of vanillin and the α-CD channel-type diffraction peaks makes the peak assignment rather complicated.…”

Section: Journal Of Agricultural and Food Chemistrymentioning

confidence: 62%

Solid Inclusion Complexes of Vanillin with Cyclodextrins: Their Formation, Characterization, and High-Temperature Stability

Kayacı

Uyar

2011

J. Agric. Food Chem.

128

View full text Add to dashboard Cite

show abstract

“…The diffraction pattern of the co-precipitate corresponded to that of the tetragonal columnar form of g-CD. [19][20][21][22] This indicated the complex formation of FBP with g-CD.…”

mentioning

confidence: 89%

Simultaneous Dissolution of Naproxen and Flurbiprofen from a Novel Ternary .GAMMA.-Cyclodextrin Complex

Higashi

Ideura

Waraya

et al. 2010

CHEMICAL & PHARMACEUTICAL BULLETIN

View full text Add to dashboard Cite

A crystalline ternary complex was prepared by sealed-heating of naproxen (NPX) with a flurbiprofen (FBP)/g g-cyclodextrin (g g-CD) inclusion complex. The dissolution rates of NPX and FBP in the ternary complex were almost the same, indicating that FBP and NPX from the complex dissolved simultaneously. The ternary CD complex showing a fascinating dissolution property could be a new formulation for combination therapies.Key words cyclodextrin; dissolution; powder X-ray diffraction; sealedheating; inclusion complex Many drug candidates usually show poor water solubility. Various pharmaceutical techniques such as polymorphic control, co-crystal formation, and nanoparticle preparation are available to improve the physicochemical properties of drugs.1-4) Cyclodextrin (CD) inclusion complex formation is also a useful technique for improving the dissolution property and enhancing the bioavailability of drugs.5-7) Co-precipitation, freeze-drying, evaporation, co-grinding, and processing with supercritical CO 2 are used for the preparation of solid CD inclusion complexes. [8][9][10] We have prepared various types of solid CD inclusion complexes by using the sealed-heating method wherein a mixture of guest and CD molecules is simply heated within an enclosed space. [11][12][13] In the sealed-heating method, vaporized guest molecules are assumed to be included in the cavity of CDs through the gas phase. Crystalline inclusion complexes of poorly water-soluble drugs can be obtained through the sealed-heating method without using solvents. Specific inclusion complexes that are difficult to prepare can also be obtained through this method. In our recent study, it was found that the sealed-heating of salicylic acid (SA) with polyethylene glycol (PEG)/g-CDpolypseudorotaxane induced complex formation.14) In this complex, two SA molecules for each g-CD molecule were incorporated into the intermolecular spaces between the columns of g-CD stacks, while double-stranded PEG chains were included in the g-CD cavity. Although a large number of studies have been carried out on the inclusion complexes of CDs, there are only a few reports on the existence of guest molecules outside the CD cavity. [15][16][17][18] New CD complexes with desired properties can be designed if the interstitial spaces outside the CD cavity are utilized for the incorporation of guest drugs. In this study, a ternary g-CD complex containing two active pharmaceutical ingredients (APIs) was prepared by the sealed-heating method. Using this method, guest drugs could be incorporated into the intermolecular spaces between g-CD columns. The dissolution property of the obtained complex was studied in order to assess its potential for pharmaceutical applications.Flurbiprofen (FBP) and naproxen (NPX) are anti-inflammatory drugs with poor water solubility (Fig. 1). In this study, each drug was used as a model guest molecule either for inclusion in the g-CD cavity or incorporation into the intermolecular spaces. The preparation process of the ternary complex consisted of two st...

show abstract

“…The channel-type assembly has been formed mainly by inclusion complexes between CDs and guest molecules, especially between CDs and ionic guest. A facile method for the preparation of channel-type assemblies from CD molecules in the absence of any guest molecules was developed by Tonelli et al (6). They succeeded in the preparation of channeltype assemblies of α-and γ-CDs by dropping an aqueous CD solution into chloroform and acetone, respectively.…”

Section: Cage-type�mentioning

confidence: 99%

Formation and Function of Nano- and Microstructures by the Self-assembly of Cyclic Oligosaccharides ‘Cyclodextrins’

Kida

2011

TIGG

View full text Add to dashboard Cite

Recently, much attention has been paid to studies on nano-and microstructures formed by the self-assembly of cyclodextrins (CDs) in the fields of supramolecular chemistry and material science. CDs can adopt various types of assembly modes in aqueous solution, as well as crystal structures. Channel-type assemblies of γ-CD (γ-CD channel ) formed unique micrometer-sized cubes and rods. By using γ-CD channel as a host, the inclusion of guest molecules dissolved in oils, which has been believed to be impossible, can be realized. Furthermore, γ-CD channel showed excellent oil dispersion, and formed organogels in a variety of oils and organic solvents at ambient temperature. This article reviews the formation behavior and function of nano-and microstructures formed by the self-assembly of CDs. A. IntroductionCyclodextrins (CDs), which are produced from starch by the action of cyclodextrin glucanotransferase, are a class of cyclic oligosaccharides consisting of several α-(1,4)-linked D-glucopyranose units (Fig. 1). CDs composed of 6, 7, and 8 glucosidic units are called α-, β-, and γ-CDs, respectively, and have been used extensively. They have a cavity of sub-

show abstract

Inclusion Compound Formation with a New Columnar Cyclodextrin Host

Cited by 173 publications

References 31 publications

Solid Inclusion Complexes of Vanillin with Cyclodextrins: Their Formation, Characterization, and High-Temperature Stability

Solid Inclusion Complexes of Vanillin with Cyclodextrins: Their Formation, Characterization, and High-Temperature Stability

Simultaneous Dissolution of Naproxen and Flurbiprofen from a Novel Ternary .GAMMA.-Cyclodextrin Complex

Formation and Function of Nano- and Microstructures by the Self-assembly of Cyclic Oligosaccharides ‘Cyclodextrins’

Contact Info

Product

Resources

About