Analysis of chiral pollutants

Capillary electrophoresis has been used for the analysis of chiral pollutants, e.g., pesticides, polynuclear-aromatic hydrocarbons, amines, carbonyl compounds, surfactants, dyes, and other toxic compounds. Moreover, CE has also been utilized to separate the structural isomers of various... 

Today, chromatographic modalities are used frequently for the analysis of chiral pollutants. The wide application of HPLC is due to the development of various chiral stationary phases and excellent reproducibility. However, ... 

In addition, some other aspects should also be addressed so that CE can be used as a routine method in this field. The most important points related to this include the development of new and better chiral selectors, detector devices, and addition of a cooling device in the CE apparatus. In addition, chiral capillaries should be developed and the CE device should be hyphenated with mass spectrometer, polarimetric, and circular dichroism detectors, which may result in good reproducibihty and improved limits of detection. The advancement of CE as a chiral analysis technique has not yet been fiilly explored and research in this direction is currently underway. In summary, there is much to be developed for the advancement of CE for the analysis of chiral pollutants. It is hoped that CE will be recognized as the technique of choice for chiral analysis of the environmental pollutants. 

Table 4 Selected GCxGC applications involving the analysis of chiral pollutants. For simplicity, only optimised experimental set-ups or those providing the most conclusive results have been mentioned (Acronyms as in Table 1)... 

Analysis of chiral pollutants by capillary electrophoresis (CE) is a new trend in separation science. This entry describes separation and identification of chiral xenobiotics by using CE. Attempts have been made to describe types of chiral selectors, applications, optimization of separations, detection strategies, mechanisms of chiral separations, CE vs chromatography and sample preparation methods. 

CE has been used for the analysis of chiral pollutants, e.g., pesticides, polynuclear aromatic hydrocarbons, amines, carbonyl compounds, surfactants, dyes, and other toxic compounds. Moreover, CE has also been utilized to separate the structural isomers of various toxic pollutants such as phenols, polyaromatic hydrocarbons, and so on. Sarac, Chankvetadze, and Blaschke " resolved the enantiomers of 2-hydrazino-2-methyl-3-(3,4-dihydroxyphenyl)propanoic acid using CD as the BGE additive. The CDs used were native, neutral, and ionic in nature with phosphate buffer as BGE. Welseloh, Wolf, and Konig investigated the CE method for the separation of biphenyls, using a phosphate buffer as BGE with CD as the chiral additive. Miura et al., used CE for the chiral resolution of seven phenoxy acid herbicides using methylated CDs as the BGE additives. Furthermore, the same group resolved 2-(4-chlorophenoxy) propionic acid (MCPP), 2-(2,4-dichlorophenoxy) propionic acid (DCPP), (2,4-dichlorophenoxy) acetic acid (2,4-D), 2-(4-chlorophenoxy) propionic acid (2,4-CPPA), [(2,4,5-... 

Today, chromatographic modalities are used frequently for the analysis of chiral pollutants. The wide application of HPLC is due to the development of various chiral stationary phases and excellent reproducibility. However, HPLC suffers from certain drawbacks, as the chiral selectors are fixed on the stationary phase and, hence, no variation in the concentrations of the chiral selectors can be carried out. Moreover, a large amount of the costly solvent is consumed to establish the chiral resolution procedure. Additionally, the poor efficiency in HPLC is due to the profile of the laminar flow, mass transfer term, and possible additional interactions of enantiomers with the residual silanol groups of the stationary phase. GC also suffers from certain drawbacks as discussed in the Introduction. ... 

Basically, the sea is the ultimate destination of any river, culvert or tributary and, therefore, it is very common to have chiral xenobiotics in marine water. Many workers have carried out qualitative and quantitative analysis of chiral pollutants in sea water. To make the concepts clear to readers, some examples are summarized here. 

The Analysis of Chiral Pollutants by High Performance Liquid Chromatography... 

Various approaches to chiral resolution have been developed for the analysis of pharmaceuticals and drugs but, unfortunately, few reports and monographs are available on the chiral separation of pollutants. Therefore, we have set out to write this book, which deals with the distribution, toxicities and art of analysis of chiral pollutants by gas chromatography and liquid chromatography that is, by high performance liquid chromatography (HPLC), sub- and supercritical fluid chromatography (SFC),... 

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