Optical activity detectors

I would like to thank Karen Fried and Maria Diez-Perez for supplying chromatograms, and Drs. Anne Aubry and Song Li for their helpful suggestions. 

(1990) Chromatographic Integration Methods, The Royal Society of Chemistry, Cambridge. 

Lingeman, H. and Underberg, W. J. M. (eds.) (1990) Detection-Oriented Derivatization Techniques, Dekker, New York. 

Parriott, D. (ed.) (1993) A Practical Guide to HPLC Detection, Academic Press, San Diego, CA. 

(1977) Liquid Chromatography Detectors, Journal of Chromatography Library, Vol. 11, Elsevier, Amsterdam. 

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Polarimetric detectors have demonstrated significant advantages for identification of optically active drug residues because optical activity is an extremely rare characteristic usually associated with biological activity. Specific rotation measurements on drug residues as they elute from the LC column have the potential to identify closely related structural analogues even when present in a compli-... 

CD spectroscopy has played an important role in the characterization of optically active molecules, and will continue to do so as long as chemists are interested in small molecules. HPLC detectors which make use of the CD effect also show great potential as being the chiroptical detectors of choice for work with dissymmetric compounds [10]. 

A general discussion regarding the instrumentation which can be used for the measurement of CD spectroscopy has been provided by Donald Bobbitt, while the more specialized requirements associated with vibrational optical activity have been discussed by Laurence Nafie. This latter chapter deals with both the methods of vibrational CD spectroscopy as well as raman vibrational optical activity. The use of CD as a detector in liquid chromatography represents an important area of heightened activity, and this has been covered by Andras Gergely. 

These advantages inherent to chiroptical detectors are particularly useful in the analysis of physiological fluids. The unique selectivity of chirality detection for LC is often due to the fact that optical activity is frequently associated with biological activity, another form of a derivatization reaction. 

Synovec and Yeung developed a highly selective and sensitive laser-based CD detector for both conventional and microbore liquid chromatography [30] and applied it to the analysis of complex mixtures of optically active metal complexes. As expected limits of detection are very low. For example for the determination of (+) trisfethylenenediamine) cobalt (HI) using an Ar-ion laser source, a microbore column, and a CD detector operating at 488 nm, the measured limit of detection is 5.6 ng. 

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