title: Separation of alpha- from beta-arylalanines by nickel nitrilotriacetate chromatography.
abstract: A method is described to separate alpha- from beta-arylalanines by ligand exchange chromatography on a nickel nitrilotriacetate agarose column with UV monitoring of the effluent. Separate mixtures containing an alpha- and beta-arylalanine pair (1 mg of each) were individually loaded onto the nickel resin pre-equilibrated with the mobile phase at room temperature, and the amino acids were eluted from the column with a gradient from pH 12.0-8.0. The beta-arylalanines eluted first, followed by the alpha-isomers. The four alpha/beta-amino acid pairs tested were well separated with baseline resolution. An aliquot of each fraction was chemically treated to derivatize the amino acids to their N-acyl methyl ester analogs, and their identities were confirmed by GC/MS analysis. The sample recovery was quantitative (>98%), and the column matrix was very resilient, as demonstrated by consistent separation of the solutes after approximately 100 preparative cycles.
authors.affiliation: Department of Chemistry, Michigan State University, East Lansing, MI 48824, USA.
authors.forename: Salinda
authors.initials: S
authors.lastname: Wijeratne
authors.forename: Noelle A
authors.initials: NA
authors.lastname: Byrne
authors.forename: Kevin D
authors.initials: KD
authors.lastname: Walker
mesh_terms: D000409:Alanine / Q000737:chemistry / Q000302:isolation & purification*; D002614:Chelating Agents / Q000737:chemistry; D002853:Chromatography, Liquid / Q000379:methods*; D008401:Gas Chromatography-Mass Spectrometry; D009571:Nitrilotriacetic Acid / Q000031:analogs & derivatives* / Q000737:chemistry; D009942:Organometallic Compounds / Q000737:chemistry*; D013056:Spectrophotometry, Ultraviolet
chemical_list: D002614:Chelating Agents; D009942:Organometallic Compounds; C088321:nickel nitrilotriacetic acid; D009571:Nitrilotriacetic Acid; D000409:Alanine