Liquid chromatography polarimetric detectors

Yeung, E.S. Polarimetric detectors, in detectors for liquid chromatography. In Detectors for Liquid Chromatography Yeung, E.S., Ed. John Wiley Sons New York, 1986 204-228. 

Currently, high-performance liquid chromatography (HPLC) methods have been widely used in the analysis of tocopherols and tocotrienols in food and nutrition areas. Each form of tocopherol and tocotrienol can be separated and quantified individually using HPLC with either a UV or fluorescence detector. The interferences are largely reduced after separation by HPLC. Therefore, the sensitivity and specificity of HPLC methods are much higher than those obtained with the colorimetric, polarimetric, and GC methods. Also, sample preparation in the HPLC methods is simpler and more efficiently duplicated than in the older methods. Many HPLC methods for the quantification of tocopherols and tocotrienols in various foods and biological samples have been reported. Method number 992.03 of the AOAC International Official Methods of Analysis provides an HPLC method to determine vitamin E in milk-based infant formula. It could probably be said that HPLC methods have become dominant in the analysis of tocopherols and tocotrienols. Therefore, the analytical protocols for tocopherols and tocotrienols in this unit are focused on HPLC methods. Normal and reversed-phase HPLC methods are discussed in the separation and quantification of tocopherols and tocotrienols (see Basic Protocol). Sample... 

Lloyd, D.K. Goodall, D.M. Scrivener, H. Diode-laser-based optical rotation detector for high-performance liquid chromatography and on-line polarimetric analysis. Anal. Chem. 1989, 61, 1238-1243. 

Boehme, W. Wagner, G. Oehme, U. Spectrophotometric and polarimetric detectors in liquid chromatography for the determination of enantiomer ratios in complex mixtures. Anal. Chem. 1982, 54, 709-711. 

Yeung, E. S., Polarimetric detectors, in Detectors for Liquid Chromatography (E. S. Yeung, ed.), John Wiley Sons, New York, 1986, pp. 204-228. 

For a characterization within a series of compounds often polarimetry supersedes CD spectroscopy because the chosen concentration for its measurement is not restricted by a too high absorption. The broad acceptance of the polarimetric standardization of chiral compounds always has been a motivation for improvements of polarimeters. Especially for the daily routine work there is a requirement for instruments with high convenience (see section on Polarimetry and CD detectors in liquid chromatography). 

A polarimetric equipment is an important detector in liquid chromatography. The combination of an [ajJmax itieasurement combined with a detection of the UV absorption allows to determine the optical purity even in the case of an incomplete chromatographic enantiomeric separation. The use of CD as a chromatographic detector is limited in liquid... 

---