Search results for "Cyclodextrin"

Separation, isolation and stereochemical assignment of imazalil enantiomers and their quantitation in an in vitro toxicity test

2016

A simple method for the separation of the enantiomers of the fungicide imazalil was developed. Racemic imazalil was separated into its enantiomers with an enantiomeric purity of 99% using HPLC-UV with an enantioselective column (permethylated cyclodextrin) operated in reversed phase mode (water with 0.2% trimethylamine and 0.08% acetic acid and methanol). The absolute configuration of the separated enantiomers was assigned and unequivocally confirmed by optical rotation as well as by vibrational circular dichroism (VCD) and electronic circular dichroism (ECD) combined with ab-initio calculations. The same enantioselective column was also used to develop an HPLC-MS/MS method for the quantifi…

Probes for studying cholesterol binding and cell biology.

2011

Cholesterol is a multifunctional lipid in eukaryotic cells. It regulates the physical state of the phospholipid bilayer, is crucially involved in the formation of membrane microdomains, affects the activity of many membrane proteins, and is the precursor for steroid hormones and bile acids. Thus, cholesterol plays a profound role in the physiology and pathophysiology of eukaryotic cells. The cholesterol molecule has achieved evolutionary perfection to fulfill its different functions in membrane organization. Here, we review basic approaches to explore the interaction of cholesterol with proteins, with a particular focus on the high diversity of fluorescent and photoreactive cholesterol prob…

Nanoassemblies of Amphiphilic Cyclodextrin and Tributyltin(IV)Complexes of meso-Tetra (4-sulfonatophenyl)porphine: Spectroscopy, Release and Cytotoxi…

2010

Catalytic properties of Ag-PolyaminoβCD NPs for reduction of nitroarenes

2014

The reduction of nitroarenes is a key reaction involved in the synthesis of several compounds such as drugs, pesticides or dyes. During the last years Pd and Ag NPs have been used as catalysts to carry out this reaction with NaBH4. However several mechanistic aspects of the process are still unclear; in particular there is not agreement about the kinetic order of these reactions, whether 0-th or 1-st order in the substrate[1]. The aim of this work is to use a novel catalytic systems constituted by Ag-NPs coated with different polyamino-βCDs (Figure 1)[2], to carry out the reduction of some aromatic nitrocompounds using NaBH4 as the reducing agent, and to determine the kinetic features of th…

Binding properties of mono-6-amino-beta-cyclodextrin towards p-nitroaniline derivatives: a polarimetric study

GEL FLUORESCENTI SUPRAMOLECOLARI FORMATI DA DERIVATI DELLA RIBOFLAVINA E β-CICLODESTRINE

2021

Cyclodextrins in capillary electrophoresis: Recent developments and new trends

2014

Despite the fact that extensive research in the field of separations by capillary electrophoresis (CE) has been carried out and many reviews have been published in the last years, a specific review on the use and future potential of cyclodextrins (CDs) in CE is not available. This review focuses the attention in the CD-CE topic over the January 2013-February 2014 period (not covered by previous more general CE-reviews). Recent contributions (reviews and research articles) including practical uses (e.g. solute-CD binding constant estimation and further potentials; 19% of publications), developments and applications (mainly chiral and achiral analysis; 38 and 24% of publications, respectively…

Fast-multivariate optimization of chiral separations in capillary electrophoresis: Anticipative strategies

2014

Abstract The design of experiments (DOE) is a good option for rationally limiting the number of experiments required to achieve the enantioresolution (Rs) of a chiral compound in capillary electrophoresis. In some cases, the modeled Rs after DOE analysis can be unsatisfactory, maybe because the range of the explored factors (DOE domain) was not the adequate. In these cases, anticipative strategies can be an alternative to the repetition of the process (e.g. a new DOE), to save time and money. In this work, multiple linear regression (MLR)-steepest ascent and a new anticipative strategy based on a multiple response-partial least squares model (called PLS2-prediction) are examined as post-DOE…

Olefin metathesis reactions with fluorinated substrates, catalysts, and solvents.

2014

Solubility and solvation features of native cyclodextrins in 1-ethyl-3-methylimidazolium acetate

2022

The comprehension of the mechanism entailing efficient solvation of cyclodextrins (CD) by green solvents is of great relevance to boost environmentally sustainable usages of smart supramolecular systems. Here, 1-ethyl-3- methylimidazolium acetate, an ecofriendly ionic liquid (IL), is considered as an excellent solvent for native CDs. This IL efficiently dissolves up to 40 wt.% β- and γ-CD already at ambient temperature and X-ray scattering indicates that CDs do not tend to detrimental flocculation under these drastic concentration conditions. Simu- lation techniques reveal the intimate mechanism of CD solvation by the ionic species: while the strong hydrogen bonding acceptor acetate anion i…