High-performance liquid chromatography selenium

NMR spectroscopy ( Se, /= 1/2, 7%) is a powerful technique for identifying cyclic selenium molecules, especially the heteroatomic ring systems that contain sulfur or tellurium in addition to selenium, for which several isomers are possible for most compositions (Section 12.1.2). Solutions of monoclinic selenium in CS2 have been shown by high-performance liquid chromatography to form an equilibrium mixture of cyclo-Seg, cyclo-Sey and cyclo-Se6. The Se NMR spectra of such solutions show two singlets that are attributable to cyclo-Seg and cyclo-Se with relative intensities that correspond to a molar ratio of ca 6 No resonance is observed for cyclo-Sey presumably as a result of the fluxional behaviour (pseudorotation) of the seven-membered ring (Section 12.1.2). 

Olivas, R.M., Donard, OXF., Gilon, N. and PotinGautier, M. (1996) Speciation of organic selenium compounds by high-performance liquid chromatography inductively coupled plasma mass spectrometry in natural waters./. Anal. At. Spectrom., 11, 1171-1176. 

Pedersen, G.A. and Larsen, E.H. (1997) Speciation of four selenium compounds using high performance liquid chromatography with on-line detection by inductively coupled plasma mass spectrometry and flame atomic absorption spectrometry Fresenius J. Anal. Chem., 358, 591-598. 

Childress, W.L., Erickson, D. and Krull, I.S. (1992) Trace selenium speciation via high-performance liquid chromatography with ultraviolet and direct-current plasma emission detection. In Element-specific Chromatographic Detection by Atomic Emission Spectroscopy (ed. Uden, PC.). American Chemical Society, Washington, DC, pp. 257-273. 

Pitts, L., A. Fisher, P. Worsfold, and S.J. Hill. 1995. Selenium speciation using high-performance liquid chromatography-hydride generation atomic fluorescence with on-line microwave reduction. J. Anal. At. Spectrom. 10 519-520. 

Bird, S.M., Ge, H., Uden, P.C., Tyson, J.F., Block, E., and Donoyer, E. 1997a High performance liquid chromatography of selenoamino acids and organo selenium compounds. Speciation by inductively coupled plasma mass spectrometry. J. Chromatogr. 789, 349-359. 

S. M. Bird, P. C. Uden, J. F. Tyson, E. Block, E. Denoyer, Speciation of selenoamino-acids and organoselenium compounds in selenium-enriched yeast using high-performance liquid chromatography Dinductively coupled plasma mass spectrometry, J. Anal. Atom. Spectrom., 12 (1997), 785D788. 

H. M. Crews, P. A. Clarke, D. J. Lewis, L. M. Owen, P. R. Strutt, A. Izquierdo, Investigation of selenium speciation in in vitro gastrointestinal extracts of cooked cod by high-performance liquid chromatography - inductively coupled plasma mass spectrometry and electrospray mass spectrometry, J. Anal. Atom. Spectrom., 11 (1996), 1177-1182. 

P. Moreno, M. A. Quijano, A. M. Gutierrez, M. C. Perez-Conde, C. Camara, Fractionation studies of selenium compounds from oysters, and their determination by high-performance liquid chromatography coupled to inductively coupled plasma mass spectrometry, J. Anal. Atom. Spectrom., 16 (2001), 1044-1050. 

Pan, R, Tyson, J.R, and Uden, P.C. Simultaneous speciation of arsenic and selenium in human urine by high-performance liquid chromatography inductively coupled plasma mass spectrometry. J. Anal Atom. Spectrom. 2007, 22, 931-937. 

Kotrebai, M., Tyson, J. E, Block, E., Uden, P. C. High-performance liquid chromatography of selenium compounds utilizing perfluorinated carboxylic acid ion-pairing agents and inductively coupled plasma and electrospray ionization mass spectrometric detection. J Chromatogr A 2000, 866, 51 63. 

D.L. Rabenstein (University of California, Riverside) is investigating the biological chemistry of selenium compounds in intact erythrocytes to characterize transport across the erythrocyte membrane and their intracellular metabolism. Reactions will be characterized in erythrocytes, plasma, and aqueous solution by nuclear magnetic resonance (NMR) spectroscopy. Methods will be developed for the determination of selenols, diselenides, and selenosulfides in biological fluids and erythrocytes by high performance liquid chromatography (HPLC) and electrochemical detection. The HPLC methods will be used to determine metabolites formed at trace levels. 

Handelman GJ, Kosted P, Short S, et al. 1989. Determination of selenium in human blood by high-performance liquid chromatography with fluorescence detection. Anal Chem 61(20) 2244-2249. 

Vezina D, Bleau G. 1988. High-performance liquid chromatography of selenium in biological samples. 

Figure 3.40 Schematic of an LC-HGAAS system (Reprinted from Analytica Chimica Acta, Niedzielski, P. The new concept of hyphenated analytical system Simultaneous determination of inorganic arsenic(lll), arsenic(V), selenium(IV) and selenium(VI) by high performance liquid chromatography-hydride generation-(fast sequential) atomic absorption spectrometry during single analysis, 55 (1-2), 199-206 T Copyright 2005 with permission from Elsevier).

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