Cyclodextrin highly sulfated

The short-end injection was also used in a paper by Perrin et al. [28]. They saw a very high chiral recognition capability of highly sulfated cyclodextrins (HS-CD). Using a test set of 27 amino acid derivatives, the application of HS-a-CD, HS-fl-CD, and HS-y-CD in a 5% w/v concentration allowed the separation of 26 compounds, of which 22 had a Rs > 2. From their experiments, a screening and optimization scheme was derived (Figure 3.3), and based on this scheme, a separation strategy was defined... 

Perrin, C., Vander Heyden, Y, Maftouh, M., Massart, D.L. Rapid screening for chiral separations by short-end injection capillary electrophoresis nsing highly sulfated cyclodextrins as chiral selectors. Electrophoresis 2001, 22, 3203-3215. 

P/ACE System MDQ chiral methods development P/ACE System MDQ highly sulfated cyclodextrin trial kit eCAP Amine Capillary Method Development Kit/Small Molecules eCAP Carbohydrate Labeling Kit... 

Rudaz, S., Calleri, E., Geiser, L., Gherkaoui, S., Prat, J., and Veuthey, J. L. (2003). Infinite enantiomeric resolution of basic compounds using highly sulfated cyclodextrin as chiral selector in capillary electrophoresis. Electrophoresis 24, 2633—2641. 

A highly sulfated 6-cyclodextrin (the tetradecasulfate) is a very effective, reliably... 

Iwata, Y. T., Garica, A., Kanamori, T., Inoue, H., Kishi, T., and Lurie, I. S. The use of a highly sulfated cyclodextrin for the simultaneous chiral separation of amphetamine-type stimulants by capillary electrophoresis. Electrophoresis, 23, 1328, 2002. 

Enantiomeric purity methods for three pharmaceutical compounds A range of a-, (i-, and y-cyclodextrins, highly and singly sulfated FSCE [153]... 

Enantioseparation of nine racemic Highly sulfated fl-cyclodextrin FSCE [159]... 

Ramstad T., Enantiomeric purity methods for three pharmaceutical compounds by electrokinetic capillary chromatography utilizing highly sulfated-y-cyclodextrin as the chiral selector. J. Chromatogr. 

Guo L., Lin S.J., Yang YE, Qi L., Wang M.X., Chen Y, Fast enantioseparation of arylglycine amides by capillary electrophoresis with highly sulfated-P-cyclodextrin as a chiral selector. J. Chromatogr. A,... 

Beider and coworkers reported the fast chiral separation of acidic and basic compounds using a commercially available quartz microchip with a simple cross-tee design and linear imaging UV detection. Highly sulfated cyclodextrins were added to the separation medium to improve selectivity and samples were loaded for 60 s using the pinched injection mode. The chiral separation of norephedrine was achieved in 2.5 s, and a mixture of three basic drugs was resolved in 11 s. 

Hgure 7 Simultaneous chiral separation of three basic drugs. Only about half of the total length of 25 mm of the microchip separation channel was needed to obtain complete resolution in 11s. Experimental conditions 25 mmol I triethylammonium phosphate buffer, pH 2.5, 5% highly sulfated y-cyclodextrin, UV detection at 200 nm. (Reproduced with permission from Ludwig M, Kohler F, and Beider D (2003) High-speed chiral separations on a microchip with UV detection. Electrophoresis 24 3233-3238 Wiley-VCH.)... 

A recent study has explored the potential of the ternary complex formed between a poly(p-cyclodextrin) (formed by polycondensation of p-cyclodextrin), a cationic surfactant (dodecyltrimethylammonium chloride), and a polyanion in water, to act as a delivery system for gene therapy,using a combination of viscometric and SANS studies as well as visual observations to determine the macroscopic and microscopic properties of the complexes. In the study, sodium dextran sulfate was used as a substitute for DNA. The potential advantages of the use of such ternary complexes over the more commonly investigated DNA-lipid or polymer complexes (lipoplexes and poly-plexes, respectively) include a high water solubility of the resulting complex (lipoplexes and polyplexes often... 

Sugiuchi H, Uji Y, Okabe H, Me T, Uekama K, Kayahara N, Miyauchi K. Direct measurement of high-density lipoprotein cholesterol in serum with polyethylene glycol-modified enzymes and sulfated alpha-cyclodextrin. Clin Chem 1995 41 717-23. 

Cyclodextrins have been used for enhancing the solubility of poorly water-soluble small molecules (Shimpi et ah, 2005). The mechanism of solubilization is formation of reversible complexes between the hydrophobic moiety of the drug molecule and the hydrophilic cyclodextrin that is highly water soluble. A similar observation has been made with some proteins and peptides (Brewster et ah, 1991 Johnson et ah, 1994 Flores et ah, 2001). Sulfated cyclodextrins and 2-hydroxypropyl-beta-cyclodextrins are approved excipients for parenteral administration, however, use of these compounds should take into consideration the cost involved. 

Electrophoretic methods are widely used alternatives for the analytical determination of the enantiomeric purity of chiral compounds [194]. Due to the high elTi-ciency of capillary electrophoresis, separations can be achieved even when very low selectivities are observed. At a preparative scale, these methods are well established for the purification of proteins and cells [195] but there is very little published on enantioselective separations. Only recently, some interest in chiral preparative applications has been manifested. Separation of the enantiomers ofterbu-taline [196] and piperoxan [197] have been reported by classical gel electrophoresis using sulfated cyclodextrin as a chiral additive, while the separation of the enantiomers of methadone could be successfully achieved by using free-fluid isotachophoresis [198] and by applying a process called interval-flow electrophoresis [199]. 

FITC-labeled amino acids as model compounds were separated in sodium dodecyl sulfate/borate buffer at pH 9.4 with y-cyclodextrin as chiral discriminator. Separation speed achieved with the microchip was one order of magnitude faster than that with conventional CE. Bailey and co-workers demonstrated chiral and achiral separation of amphetamine and analogous compounds labeled with 4-fluoro-7-nitrobenzofurazane on an S-folded separation channel. Phosphate buffer with sulfated y-cyclodextrin and sodium dodecyl sulfate as additives was used. It is expected that chiral separations on microfabricated electrophoresis devices with high speed and high throughput will find its way into pharmaceutical and biomedical sciences as well as into other areas. 

F Benavente, RA Jackson, JV Weber, NA Guzman. Use of non-aqueous capillary electrophoresis containing sulfated alpha-cyclodextrin for the separation and characterization of a water insoluble drug substance. 24th Int Symp on High Performance Liquid Phase Separations and Related Techniques HPLC 2000, Seattle, WA, abstr P-0732, 2000. 

Hydrazine can be stabilized by formation of an inclusion compound with hydroquinone.58 Uncomplexed anhydrous hydrazine can be explosive. Highly toxic dimethyl sulfate can be handled more easily as an inclusion compound with toxic 18-crown-6. Both of these toxic compounds could be avoided through the use of dimethyl carbonate (as described in Chap. 2). Reactive intermediates, such as benzyne, have been stabilized by generating them inside hosts.59 Even the noble gas xenon can be trapped reversibly by hosts such as a cryptophane, 4-ferf-butyl-calix[4]arene or a-cyclodextrin.60... 

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