title: An isocratic separation of underivatized gentamicin components, 1H NMR assignment and protonation pattern.
abstract: A simple method for the separation of the major components of commercial gentamicin sulfate (C-1, C-1a, C-2, C-2a) by high-performance liquid chromatography (HPLC) on an analytical and a semipreparative scale was developed. The method utilized ion-pair reversed-phase chromatography, isocratic elution with an aqueous solution containing 9% trifluoroacetic acid and 2.5% acetonitrile as the mobile phase at a flow rate of 2 and 9 mL/min for analytical and semipreparative columns, respectively. Detection was carried out at 213 nm without derivatization. The protonation pattern of the separated gentamicins was determined by potentiometry and 15N and 1H NMR. The full proton NMR assignment for gentamicin C-1 was obtained through the use of 1H 1D and 2D 1H-1H COSY measurements.
authors.affiliation: Department of Otolaryngology, Kresge Hearing Research Institute, University of Michigan, 1331 E Ann, Ann Arbor, MI 48109-0506, USA.
authors.forename: Wojciech
authors.initials: W
authors.lastname: Lesniak
authors.forename: John
authors.initials: J
authors.lastname: Mc Laren
authors.forename: Wesley R
authors.initials: WR
authors.lastname: Harris
authors.forename: Vincent L
authors.initials: VL
authors.lastname: Pecoraro
authors.forename: Jochen
authors.initials: J
authors.lastname: Schacht
mesh_terms: D000097:Acetonitriles / Q000737:chemistry; D000588:Amines / Q000737:chemistry; D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000302:isolation & purification; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D005839:Gentamicins / Q000737:chemistry / Q000302:isolation & purification*; D006863:Hydrogen-Ion Concentration; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D008970:Molecular Weight; D011199:Potentiometry; D011522:Protons; D021241:Spectrometry, Mass, Electrospray Ionization; D014269:Trifluoroacetic Acid / Q000737:chemistry
chemical_list: D000097:Acetonitriles; D000588:Amines; D000900:Anti-Bacterial Agents; D005839:Gentamicins; D011522:Protons; C100093:gentamicin C; D014269:Trifluoroacetic Acid; C032159:acetonitrile