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Marfey's Reagent (marfey + reagent)
Selected AbstractsMarfey's reagent: Past, present, and future uses of 1-fluoro-2,4-dinitrophenyl-5-L-alanine amideJOURNAL OF SEPARATION SCIENCE, JSS, Issue 1-2 2003Clayton B'Hymer Abstract This article describes some of the uses of Marfey's reagent, 1-fluoro-2,4-dinitrophenyl-5-L-alanine amide (FDAA), a pre-column derivatizing reagent for the separation of enantiomeric isomers of amino acids and amine compounds. An introduction to the basic implementation of this reagent and its historical development are presented. Actual uses in amino acid, short peptide, and pharmaceutical compounds are included, as well as the advantages and disadvantages over other pre-column derivatization techniques and direct chromatographic separations. Applications of current interest, including its use as an orthogonal analysis and in enantiomeric purity analysis of selenoamino acids using element specific detection, are also discussed. [source] HPLC determination of acidic d -amino acids and their N -methyl derivatives in biological tissuesBIOMEDICAL CHROMATOGRAPHY, Issue 6 2009Mara Tsesarskaia Abstract d -Aspartate (d -Asp) and N -methyl- d -aspartate (NMDA) occur in the neuroendocrine systems of vertebrates and invertebrates, where they play a role in hormone release and synthesis, neurotransmission, and memory and learning. N -methyl- d -glutamate (NMDG) has also been detected in marine bivalves. Several methods have been used to detect these amino acids, but they require pretreatment of tissue samples with o -phthaldialdehyde (OPA) to remove primary amino acids that interfere with the detection of NMDA and NMDG. We report here a one-step derivatization procedure with the chiral reagent N-, -(5-fluoro-2,4-dinitrophenyl)-(d or l)-valine amide, FDNP-Val-NH2, a close analog of Marfey's reagent but with better resolution and higher molar absorptivity. The diastereomers formed were separated by HPLC on an ODS-Hypersil column eluted with TFA/water,TFA/MeCN. UV absorption at 340 nm permitted detection levels as low as 5,10 pmol. d -Asp, NMDA and NMDG peaks were not obscured by other primary or secondary amino acids; hence pretreatment of tissues with OPA was not required. This method is highly reliable and fast (less than 40 min HPLC run). Using this method, we detected d -Asp, NMDA and NMDG in several biological tissues (octopus brain, optical lobe and bucchal mass; foot and mantle of the mollusk Scapharca broughtonii), confirming the results of other researchers. Copyright © 2009 John Wiley & Sons, Ltd. [source] Fast chiral separation of drugs using columns packed with sub-2 ,m particles and ultra-high pressureCHIRALITY, Issue 3 2010Davy Guillarme Abstract The use of columns packed with sub-2 ,m particles in liquid chromatography with very high pressure conditions (known as UHPLC) was investigated for the fast enantioseparation of drugs. Two different procedures were evaluated and compared using amphetamine derivatives and ,-blockers as model compounds. In one case, cyclodextrins (CD) were directly added to the mobile phase and chiral separations were carried out in less than 5 min. However, this strategy suffered from several drawbacks linked to column lifetime and low chromatographic efficiencies. In the other case, the analysis of enantiomers was carried out after a derivatization procedure using two different reagents, 2,3,4-tri-O-acetyl-,- D -arabinopyranosyl isothiocyanate (AITC) and N -,-(2,4-dinitro-5-fluorophenyl)- L -alaninamide (Marfey's reagent). Separation of several amphetamine derivatives contained within the same sample was achieved in 2,5 min with high efficiency and selectivity. The proposed approach was also successfully applied to the enantiomeric purity determination of (+)-(S)-amphetamine and (+)-(S)-methamphetamine. Similar results were obtained with ,-blockers, and the separation of 10 enantiomers was carried out in less than 3 min, whereas the individual separation of several ,-blocker enantiomers was performed in 1 min or less. Chirality, 2010. © 2009 Wiley-Liss, Inc. [source] | ||||||||||