Article

Recognition-induced supramolecular porous nanosphere formation from cyclodextrin conjugated by cholic acid.

Department of Chemistry, State Key Laboratory of Elemento-Organic Chemistry, Nankai University, Tianjin 300071, People's Republic of China.
Langmuir (Impact Factor: 4.38). 04/2006; 22(7):3434-8. DOI: 10.1021/la052434j
Source: PubMed

ABSTRACT A supramolecular porous nanosphere is constructed from amphiphilic cholic acid-modified cyclodextrin triggered by guest sodium 1-naphthylamino-4-sulfonate and is comprehensively characterized by nuclear magnetic resonance (NMR), light scattering, transmission electron microscopy, and gas adsorption experiments. The results obtained show that the porous nanosphere with the radius of 25-35 nm has moderate nitrogen adsorption ability. Further NMR, circular dichroism, and the fluorimetric titrations on the self-assembling behavior in aqueous solution reveal that the substituting group of the guest molecule and pH values are the key to induce the formation of the porous nanosphere.

0 Bookmarks
 · 
50 Views
  • [Show abstract] [Hide abstract]
    ABSTRACT: Not Available
    Network Operations and Management Symposium, 1992. NOMS '92. Networks Without Bounds., IEEE 1992; 05/1992
  • [Show abstract] [Hide abstract]
    ABSTRACT: This review discusses drawbacks to peptide and protein oral formulations related to these drugs' chemical and physical instability. Means used to overcome such limitations are mentioned and discussed in parallel with manufacturing considerations, metabolism, absorption mechanisms and the efflux systems that peptides and proteins experience as they travel through the gastrointestinal tract. Special focus is given to the use of delivery systems based on nanoparticles and cyclodextrins. Advantages of these systems relate to the protection from degradation, enhancement of absorption, targeting and controlling the release of the drug. Biodistribution and safety issues are discussed once material from the delivery system is expected to be absorbed by the body and thus interact with biological components. Operating parameters regarding nanoparticle manufacture and composition are also overviewed since nanoparticle physicochemical characteristics influence the ability to successfully entrap the intended drug as well as interaction with body.
    Nanomedicine 05/2007; 2(2):183-202. · 5.26 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Three naphthalene-modified cyclodextrins (CDs) 3–5 were synthesized as supramolecular chiral photosensitizing hosts for enantiodifferentiating photoisomerization of (Z,Z)-1,3-cyclooctadiene (1ZZ) to its E,Z-isomer (1EZ). In aqueous methanolic solutions, β-CD-based sensitizer 4 binds 1ZZ in its chiral cavity much more strongly than α- and γ-CD homologues 3 and 5. Accelerated, often static, fluorescence quenching of these naphthalene-modified CDs was observed upon inclusion of 1ZZ. The photoisomerization of 1ZZ mediated by 3–5 yielded enantiomeric 1EZ in modest yields. The enantiomeric excesses (ee’s) obtained with α- and β-CD-based sensitizers 3 and 4, both of which have relatively small cavities, are less sensitive to temperature, demonstrating the low-entropy nature of the α- and β-CD complexes. In contrast, increasing reaction temperature significantly diminished the product’s ee and even caused a switching of enantioselectivity upon photoisomerization sensitized by γ-CD-based 5, revealing that the entropy factor plays a crucial role in the wide cavity of γ-CD.
    New Journal of Chemistry 01/2007; 31(5). · 2.97 Impact Factor

Full-text

View
0 Downloads
Available from