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A bis(beta-cyclodextrin)- fullerene conjugate linked at the secondary hydroxyl side is prepared in a good yield from its precursor N.N-bis(2-(2-aminoethylamino)ethyl)malonamide-bridged bis(beta-cyclodextrin). The spectrophotometric study of fluorescence sensing and circular dichroism spectroscopy showed that the bis(beta-cyclodextrin)-fullerene conjugate displayed an intramolecular capsulate-type conformation in aqueous solution.

The design and fabrication of biocompatible mechanized phosphonate-clothed silica nanoparticles in which the supramolecular machinery covering the surfaces of the nanoparticles behaves like nanopistons, releasing encapsulated guest molecules in a controlled fashion under acidic conditions is described. The results obtained provide a significant pathway for the development of pH-responsive nanoparticle-based dual drug delivery vehicles that has potentially capability to be interfaced with biological systems.

A series of mechanized silica nanoparticles which have the ability to deliver cargo molecules employing a series of nanovalves under abiotic conditions is described. The newly designed MSNP delivery system is capable of drug delivery based on the function of [beta]-cyclodextrin ([beta]-CD) nanovalves that are responsive to the endosomal acidification conditions in human differentiated myeloid (THP-1) and squamous carcinoma (KB-31) cell lines.

The fabrication of light-operated mechanized nanoparticles (NPs) that are able to retain and release dye molecules upon exposure to light is described. The ability of mechanized NPs with hydrophilic feature to release stored drug molecules in response to an external light source could find application in light-operated intracellular drug delivery system.

A pyrene-modified [beta]-cyclodextrin (pyrenecyclodextrin)-decorated single-walled carbon nanotube (SWNT) field-effect transistor (FET) device is fabricated, which has served as a tunable photosensor to sense a fluorescence adamantyl-modified Ru complex (ADA-Ru). The present photosensor has displayed a promising application in the area of tunable light detection, as these photoresponse processes are recoverable following the removal of the light.

The operation of a redox-switchable [alpha]-cyclodextrin (CD)-based [2]rotaxane is studied by using the spectroscopic and electrochemical probes. The [alpha]-CD ring in the [2]rotaxane moves between a TTF unit, the more preferred station and a triazole ring system, the less preferred station, under redox control.

The article presents a comparative study of the comparative properties, gelation behavior and self-organization of a cholesterol-stoppered bistable [2]rotaxane and its dumbbell precursor. The compounds are found to be useful for the formation of organogels also.

Two beta-cyclodextrin (beta-CD) derivatives bearing steroid groups are synthesized by the condensation of mono(6-aminoethylamino-6-deoxy)-beta-CD with cholic acid and deoxycholic acid, respectively, and their original conformations and binding behavior to the organic anion of naphthalenesulfonate derivatives are examined by using NMR spectroscopy and spectrofluorometric titration methods. The cholic acid or deoxycholic acid modified beta-CD could act as an anion reorganization probe to dominate the molecular and size/shape recognition of guests.

Two novel beta-cyclodextrin (beta-CD) derivatives possessing azobenzene functional groups as a spectral probe were synthesized in high yields and their complexation behaviors with aliphatic alcohols were evaluated by using UV-vis, circular dichroism and 1H NMR spectroscopy.

The study conducted to prepare two channel-type supramolecular aggregations by the inclusion complex of beta-cyclodextrin with 2,2-dipyridine and 4,4-dipyridine is presented. Its binding abilities and assembly behavior in solution and the solid state by means of X-ray crystallography are investigated.

A deoxycholic acid-modified β-cyclodextrin derivative (2) and an azobenzene-branched poly(acrylic acid) copolymer (3) were prepared, and the association and dissociation of 2with the trans/cis-azobenzene units in 3were characterized by UV/vis spectroscopy, induced circular dichroism, and 1H NMR spectroscopy. The experimental results indicate that the trans-azobenzene units are bound strongly within the cavities of 2whereas the cis-azobenzene is not bound at all. A supramolecular inclusion complex (1), formed by 2and 3, is accompanied by the formation of a hydrogel. The light-responsive gel-to-sol and sol-to-gel phase transitions of the hydrogel, induced by trans-cisphotoisomerization of the azobenzene units, were investigated. In the hydrogel system, the trans-azobenzene units in 3are included inside the hydrophobic cavity of 2. Upon photoirradiation with UV light of 355 nm, the hydrogel is converted efficiently to the sol phase because the trans-azobenzene units are converted photochemically to their cis configurations, whereupon the resulting cis-azobenzene units dissociate from 2. The hydrogel can be recovered from the sol phase by photoirradiation with visible light of 450 nm. The swelling ratio for fresh hydrogel samples, which was found to be 8.7 ± 0.7, was measured for a number of gel-to-sol and sol-to-gel phase-transition cycles. [ABSTRACT FROM AUTHOR]

Two β-cyclodextrin (8-CD) derivatives bearing steroid groups (1 and 2) were synthesized by the condensation of mono(6-aminoethylamino-6-deoxy)-β-CD with cholic acid and deoxycholic acid, respectively, and their original conformations and binding behavior to the organic anion of naphthalenesulfonate derivatives were investigated by using ¹H NMR spectroscopy and spectrofluorometric titration in combination with computational methods. The 2D NMR experiments reveal that the steroid groups attached to the β-CD rim could be deeply embedded in the β-CD cavity to form the intramolecular (for 1) or intermolecular (for 2) inclusion complexes in aqueous solution. Upon complexation with naphthalenesulfonate derivatives, modified β-CDs display two obviously different binding modes, that is, the competitive inclusion mode and the induced-fit inclusion mode, which is consistent with the results of molecular modeling study. The two modes and the strict size/shape fitting relationship between the hosts and guests reasonably explain the different binding behaviors and molecular selectivity of host β-CDs 1 and 2 toward the naphthalenesulfonate guests. Therefore, the cholic acid- or deoxycholic acid-modified β-CDs could effectively recognize the size/shape of guest molecules as compared with the parent β-CD, giving good molecular selectivity up to 24.9 for the disodium 2,6-naphthalenedisulfonate/disodium 1,5-naphthalenedisulfonate pair by the host 1. [ABSTRACT FROM AUTHOR]

The article provides information on the chemical modifications of the light-induced nanoparticles and its significance in releasing regulated drugs. According to the article, it explores their limitation in manipulating the restructured drug delivery systems and cites the efficacy of light in changing the chemical structure. Further, it mentions the chemical compounds that are used in chemical modification including azobenzene and benzoic acid.

The article reports the use of spectroscopic and electrochemical probes on a redox-switchable α -cyclodextrin-based [2]rotaxane. The authors distinguish the property of this [2]rotaxane and its consequences for design, synthesis and fabrication of nanoscale systems. Moreovers, the authors added that the results of their analysis can aid drug delivery for diseased cells.

The article reports on the preparation of new fluorescent polypseudorotaxanes by threading the anthryl-modified cyclodextrin onto the polypropylene glycol. Spectrophotometric and microscopic studies demonstrate that the polypseudorotaxanes show good binding abilities to calf thymus DNA. The polypseudorotaxanes can efficiently condense the free DNA to particulate structures.