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Winkler, Roland G.; Fioravanti, Stefania; Ciccotti, Giovanni; Margheritis, Chiara; Villa, M.

doi:10.1023/a:1008155230143

Cited by 49 publications

(32 citation statements)

References 6 publications

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“…The hygroscopic property of b-CD is because the outside of the b-CD torus shape is typically hydrophilic and water molecules are easily adsorbed, and the cavity also contains weak hydrophilic and water binding sites (Martin Del Valle, 2004;Tanada, Nakamura, Kawasaki, Kurihara, & Umemoto, 1996). From crystallographic study (Lindner & Saenger, 1982) and molecular dynamics simulation study (Winkler, Fioravanti, Ciccotti, Margheritis, & Villa, 2000), it was reported that b-CD is associate with 12 water molecules to form a dodecahydrate. Our result of 12.36 mol of water absorbed by b-CD is in agreement with the reports.…”

Section: Resultsmentioning

confidence: 99%

Effect of encapsulation of d-limonene on the moisture adsorption property of β-cyclodextrin

Fang

Comino

Bhandari

2013

LWT - Food Science and Technology

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Section: Resultsmentioning

confidence: 99%

Effect of encapsulation of d-limonene on the moisture adsorption property of β-cyclodextrin

Fang

Comino

Bhandari

2013

LWT - Food Science and Technology

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“…The cavity of "empty" βCD can admit -five to six water molecules [12]; therefore, the value I 3 /I 1 = 1.55 corresponds to the vibronic structure of the fluores cence spectrum of pyrene involved in the aggregate (H 2 O) n ⋅ (Py@4βCD), where n = 10-12, and, starting from this value, I 3 /I 1 further increases after the addi tion of other analytes. We obtained values of I 3 /I 1 for analytes of different polarity (benzene, toluene, hex ane, cyclohexane, and methylcyclohexane) and polar liquids (ethanol, acetone, and acetonitrile).…”

Section: Change In the Vibronic Structure Of Pyrene Fluorescence Specmentioning

confidence: 99%

Vibronic structure of electronic absorption and fluorescence spectra of pyrene in the complex with β-cyclodextrin in the presence of nonpolar and polar solvents

et al. 2015

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The feasibility of using pyrene as a fluorescent probe in complexes cyclodextrin-pyrene-analyte in aqueous solutions was studied for several analytes (A) of different polarity. Bands that prove the formation of the complex Py 2 βCD were found for the first time in the UV-VIS spectrum of an aqueous solution of pyrene in the presence of β cyclodextrin. A characteristic of a fluorescent probe is the ratio I 3 /I 1 in the fluo rescence spectrum, where I 3 is the intensity of the third vibronic line at ~800 cm -1 , and I 1 is the intensity of the 0-0 transition. The value of I 3 /I 1 for Py 2 βCD is highly sensitive to the addition of an analyte with a con centration of several μM/L to the aqueous solution. Dependences of (I 3 /I 1 )/C on the function of the dielec tric constant ε of the analyte fε= (ε -1)/(2ε + 1) are divided into two straight lines with different slopes for nonpolar and polar solvents. Energies of insertion of analytes into Py 2 βCD were calculated by the quantum chemical PM3 method. An increase in (I 3 /I 1 )/C corresponds to the more thermodynamically stable complex 2APy 2 βCD.

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“…Molecular dynamics (MD) simulations are more timeconsuming but provide a better connection between atomistic constitution and macroscopic properties when compared to pure geometry optimizations methods. 29 In addition to structural [30][31][32]35,36,39,41 and solvation 33,34,[37][38][39][40][41][42][43] aspects, dynamic information can be monitored. The latter is essential to the understanding of the properties and mechanisms involved in host-guest complexation.…”

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confidence: 99%

Revisiting the internal conformational dynamics and solvation properties of cyclodextrins

Pereira¹,

Moura²,

Freitas³

et al. 2007

J. Braz. Chem. Soc.

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Simulações de dinâmica molecular são utilizadas para investigar a dinâmica conformacional interna e propriedades de solvatação das três ciclodextrinas naturais, α-, β-e γ-ciclodextrina em água e temperatura ambiente. Estes oligossacarídeos derivados da glicose apresentam uma estrutura molecular peculiar que lhes confere a habilidade de formar complexos de inclusão e modificar as propriedades físico-químicas das moléculas complexadas. As características estruturais das ciclodextrinas em solução são determinantes para a complexação. As análises das trajetórias obtidas mostram que ligações de hidrogênio secundárias entre resíduos de glicose adjacentes estão presentes em solução e apresentam um caráter altamente dinâmico, onde ligações de hidrogênio alternativas podem ser formadas com moléculas de água. Apesar do baixo caráter hidrofílico, as cavidades apresentam-se solvatadas e o número de moléculas de água dentro da cavidade é aproximadamente duplicada por unidade de glicose adicionada ao macrociclo. Os tempos de residência para as moléculas de água dentro das cavidades são inversamente proporcionais ao seu respectivo tamanho.Molecular dynamics simulations were used to investigate the internal conformational dynamics and solvation properties of the three natural cyclodextrins, α-, β-and γ-cyclodextrin in aqueous solution at room temperature. These glucose-derived oligosacharides present a molecular structure that confers them the ability to complex guest molecules and change their physicochemical properties. The structural behavior of cyclodextrins in solution is crucial for their complexation abilities. Analyses of the obtained trajectories show that inter-glucose hydrogen bonds between the secondary hydroxyl groups are present in solution, but show a very dynamical character where alternative hydrogen bonds to water molecules can be formed. Despite the lower hydrophilicity of the cyclodextrins inner-cavities, they were found to be solvated and the number of water molecules inside the cavity roughly doubles per glucose unit added to the ring. The residence times for water molecules inside the cavities are inversely proportional to the cavity size. Keywords: cyclodextrins, molecular dynamics, solvation, flexibility IntroductionCyclodextrins (CDs) have been extensively studied since their discovery in the late nineteenth century.1 Their peculiar properties and behavior have interested scientists in many different fields.2 These cyclic oligosaccharides, obtained from starch by glucanotransferase degradation, are formed by a certain number of α-D-glucopyranose units linked by α(1→4) glycosidic bonds. This arrangement produces a truncated cone shape with a central cavity relatively hydrophobic and an external surface relatively hydrophilic.1-3 Naturally occurring CDs, known as α-, β-and γ-CD, present six, seven and eight glucose units, respectively.1-3 The structural features of these saccharides allow them to form inclusion complexes with a great variety of compounds.3 Due to their ability to form host-guest complexe...

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Untitled

Cited by 49 publications

References 6 publications

Effect of encapsulation of d-limonene on the moisture adsorption property of β-cyclodextrin

Effect of encapsulation of d-limonene on the moisture adsorption property of β-cyclodextrin

Vibronic structure of electronic absorption and fluorescence spectra of pyrene in the complex with β-cyclodextrin in the presence of nonpolar and polar solvents

Revisiting the internal conformational dynamics and solvation properties of cyclodextrins

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