High Using chiral stationary phases

As yet, the number of applications is limited but is likely to grow as instrumentation, mostly based on existing CE systems, and columns are improved and the theory of CEC develops. Current examples include mixtures of polyaromatic hydrocarbons, peptides, proteins, DNA fragments, pharmaceuticals and dyes. Chiral separations are possible using chiral stationary phases or by the addition of cyclodextrins to the buffer (p. 179). In theory, the very high efficiencies attainable in CEC mean high peak capacities and therefore the possibility of separating complex mixtures of hundreds of... 

Pirkle, W.H., Finn, J.M., Schreiner, J.L., and Hamper, B.C. (1981) A widely useful chiral stationary phase for the high-performance liquid chromatography separation of enantiomers, J. Am. Chem. Soc. 103, 3964-3966. 

Caccamese, S. Direct high-performance liquid chromatography (HPLC) separation of etodolac enantiomers using chiral stationary phases. Chirality, 1993, 5, 164-167... 

W. H. Pirkle, J. M. Finn, J. L. Schreiner and B. C Hamper, A Widely Useful Chiral Stationary Phase for the High-Performance Liquid Chromatography Separation of Enantiomers, J. Am. Chem. Soc., 103 (1981) 3964. 

Chiral resolution in GC is carried out using chiral stationary phases (CSPs) that is, GC columns containing chiral compounds. Many chiral compounds are used for the preparation of chiral stationary phases. The most commonly used chiral compounds are cyclodextrins (CD) and their derivatives. The merit of CD derivatives for chiral resolution in GC is the great spectmm of resolvable classes of compounds. The modified CDs are capable of resolving chiral pollutants over a high range of GC temperatures. 

Chen XM, Yamamoto C, Okamoto Y (2007) Polysaccharide derivatives as useful chiral stationary phases in high-performance liquid chromatography. Pure Appl Chem 79 1561-1573... 

Thin-Layer Chromatography. Chiral stationary phases have been used less extensively in tic as in high performance Hquid chromatography (hplc). This may, in large part, be due to lack of avakabiHty. The cost of many chiral selectors, as well as the accessibiHty and success of chiral additives, may have inhibited widespread commerciali2ation. Usually, nondestmctive visuali2ation of the sample spots in tic is accompHshed using iodine vapor, uv or fluorescence. However, the presence of the chiral selector in the stationary phase can mask the analyte and interfere with detection (43). 

Gyclodextrins. As indicated previously, the native cyclodextrins, which are thermally stable, have been used extensively in Hquid chromatographic chiral separations, but their utihty in gc appHcations was hampered because their highly crystallinity and insolubiUty in most organic solvents made them difficult to formulate into a gc stationary phase. However, some functionali2ed cyclodextrins form viscous oils suitable for gc stationary-phase coatings and have been used either neat or diluted in a polysiloxane polymer as chiral stationary phases for gc (119). Some of the derivati2ed cyclodextrins which have been adapted to gc phases are 3-0-acetyl-2,6-di-0-pentyl, 3-0-butyryl-2,6-di-0-pentyl,... 

Despite the difficulties caused by the rapidly expanding literature, the use of chiral stationary phases (CSPs) as the method of choice for analysis or preparation of enantiomers is today well established and has become almost routine. It results from the development of chiral chromatographic methods that more than 1000 chiral stationary phases exemplified by several thousands of enantiomer separations have been described for high-performance liquid chromatography (HPLC). 

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