title: Purification and biochemical characterization of xanthopterin from patients with chronic renal failure. I. Isolation, purification and preliminary characterization.
abstract: We describe the purification and initial characterization of a hitherto unrecognized fluorescence (excitation/emission maxima at 380/440 nm and 400/460 nm) reported from this laboratory in patients with chronic renal failure (Clin Chem 31: 1988, 1985). Purification was achieved using Sephadex G-10 gel chromatography combined with reverse phase and ion exchange high-performance liquid chromatography (HPLC). Purity of the "blue-green" fluorescent compound was determined to be greater than 99% by HPLC, and two-dimensional thin layer chromatography using an acidic and basic solvent system. The excitation/emission maxima were shown to be 390 nm/456 nm, and ultraviolet scans, at pH 1.0, 7.0, and 13.0, gave absorbance optima at 261 nm/356 nm, 278 nm/390 nm, and 255 nm/394 nm, respectively. The isoelectric point of 4.05 in conjunction with the fluorescent and ultraviolet spectra suggests that the fluorophore belongs to the class of compounds known as pteridines.
authors.affiliation: Department of Biochemistry, Rush University, Chicago, IL.
authors.forename: R H
authors.initials: RH
authors.lastname: Williams
authors.forename: M
authors.initials: M
authors.lastname: Shaykh
authors.forename: S
authors.initials: S
authors.lastname: Ahmed
authors.forename: T
authors.initials: T
authors.lastname: Musiala
authors.forename: N
authors.initials: N
authors.lastname: Bazilinski
authors.forename: G
authors.initials: G
authors.lastname: Dunea
authors.forename: A
authors.initials: A
authors.lastname: Dubin
mesh_terms: D002851:Chromatography, High Pressure Liquid; D006801:Humans; D007676:Kidney Failure, Chronic / Q000097:blood*; D013057:Spectrum Analysis; D014976:Xanthopterin / Q000737:chemistry / Q000302:isolation & purification*
chemical_list: D014976:Xanthopterin