Search results for " Cyclodextrin"
showing 10 items of 46 documents
Chiral recognition of protected amino acids by means of fluorescent binary complex pyrene/heptakis-(6-amino)-(6-deoxy)-β-cyclodextrin
2006
The ability of the binary complex pyrene (Py)/heptakis-(6-amino)-(6-deoxy)-β-cyclodextrin (am-β-CD) to act as a chiral selector was tested at two pH values (8.0 and 9.0). Phenylalanine (Phe), methionine (Met) and histidine (His) were used as chiral model molecules. The stability of ternary complexes Py/am-β-CD/amino acid was determined by means of spectrofluorimetric measurements. The data collected showed an increase in stability going from the binary to ternary complex and above all the possibility to use the binary complex as a chiral selector. Finally, data collected at two pH values showed that the binary complex is a better chiral selector when charged rather than in its neutral form.
Aggregation in aqueous media of tri-block copolymers tuned by the molecular selectivity of cyclodextrins
2009
The water + cyclodextrin + poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) mixtures have been investigated to explore the temperature effect on the aggregation of the copolymer in the presence of cyclodextrins (CDs). The CDs with different cavity sizes were chosen because they may include either the hydrophilic poly(ethylene oxides) block or both kinds of blocks. The differential scanning calorimetry and viscosity experiments straightforwardly evidenced that the critical micellar temperature is shifted to larger values by adding a CD which is able to include the middle poly(propylene oxide) block while it is not influenced by the presence of CD which is selective to the poly…
Effect of pH Variations on the Properties of Cyclodextrin‐Calixarene Nanosponges
2019
The pH-responsive properties of cyclodextrin-calixarene nanosponge co-polymeric materials have been investigated. In particular, ISE-H+ potentiometric titrations were carried out in order to evaluate the acid-base properties and the actual amount of ionizable sites present in the materials. Moreover, the relevant pH-dependent adsorption abilities were evaluated towards a set of selected model organic pollutant molecules by means of adsorption tests and by studying the corresponding adsorption isotherms. The latter ones could be suitably described by means of the Freundlich model. The whole of the experimental results enabled us to clarify some general aspects of the microscopic behavior of …
Binding abilities of new cyclodextrin-cucurbituril supramolecular hosts
2015
Various combined techniques (UV–vis spectrophotometry, isothermal titration calorimetry, thermogravimetry, ESI-MS mass spectrometry, polarimetry and 1H NMR spectroscopy) were used in order to study the interaction between a new combined supramolecular host, namely a bow-tie-structured cyclodextrin–cucurbituril association solely held by non-covalent interactions, and a suitably selected guest, namely the N-(p-nitrophenyl)-1,8-diaminooctane hydrochloride. In particular, the use of different techniques highlighted the peculiar features of the possible host–guest supramolecular interactions under different concentration conditions.
Modulating the Self-assembly of Block Copolymers by Selective Cyclodextrins
2009
Effect on the block copolymer self-assembling in water of block selective cyclodextrin addition
2008
AQUEOUS MIXTURES OF A THERMOSENSITIVE CATIONIC BLOCK COPOLYMER AND CYCLODEXTRINS. INCLUSION COMPLEXES FORMATION.
2010
Modulating the self-assembly of thermosensitive block copolymers by selective cyclodextrins
2009
HYALURONIC ACID/-CYCLODEXTRINS HYDROGEL FOR CORNEAL RELEASE OF EPITHELIAL CELLS AND DEXAMETHASONE
2015
Recycling of almond by-products for intestinal inflammation: improvement of physical-chemical, technological and biological characteristics of a drie…
2020
Background: Almond skins are rich in bioactive compounds that undergo oxidation/degradation phenomena and are poorly soluble in water, reducing in vivo absorption and bioavailability, factors that influence the pharmacological activity of an active product. We developed a dried acetonic almond skins extract/cyclodextrin complex to improve extract solubility, dissolution rate and biological activity. Methods: A lyophilized acetonic almond skin extract was produced. To optimize complex formulation, phase solubility studies and complex characterization (absorption studies, differential scanning calorimetry (DSC), morphology, solubility studies) were performed. To evaluate a possible use in hea…