title: Enantiomers separation by nano-liquid chromatography: use of a novel sub-2 μm vancomycin silica hydride stationary phase.
abstract: A novel sub-2 μm chiral stationary phase (CSP) was prepared immobilizing vancomycin onto 1.8 μm diol hydride-based silica particles. The CSP was packed into fused silica capillaries of 75 μm i.d. with a length of 11 cm and evaluated by means of nano-liquid chromatography (nano-LC) using model compounds of both pharmaceutical and environmental interest (some non-steroidal anti-inflammatory drugs, β-blockers and herbicides). The study of the effect of the linear velocity of the mobile phase on chromatographic efficiency showed good enantioresolutions up to a value of 5.11 at the optimal linear velocity with efficiencies in terms of number of plates per meter in the range 51,650-68,330. The results were compared with the ones obtained employing 5 μm vancomycin modified diol-silica particles packed in capillaries of the same i.d. For the acidic analytes the sub-2 μm CSP showed better performances, the baseline chiral separation of several studied compounds occurred in an analysis time of less than 3 min. Column-to-column packing reproducibility (n=3) expressed as relative standard deviation was in the range 2.2-5.8% and 0.5-7.7% for retention times and peak areas, respectively.
authors.affiliation: Institute of Chemical Methodologies, Italian National Research Council (C.N.R.), Via Salaria km 29, 300-00015 Monterotondo (Rome), Italy; Department of Physical and Chemical Sciences, University of L'Aquila, 67100 Coppito (L'Aquila) Italy.
authors.forename: Silvia
authors.initials: S
authors.lastname: Rocchi
authors.affiliation: Institute of Chemical Methodologies, Italian National Research Council (C.N.R.), Via Salaria km 29, 300-00015 Monterotondo (Rome), Italy.
authors.forename: Anna
authors.initials: A
authors.lastname: Rocco
authors.affiliation: Department of Chemistry, San José State University, San José, CA 95112, United States.
authors.forename: Joseph J
authors.initials: JJ
authors.lastname: Pesek
authors.affiliation: Department of Chemistry, San José State University, San José, CA 95112, United States.
authors.forename: Maria T
authors.initials: MT
authors.lastname: Matyska
authors.affiliation: Institute of Chemical Methodologies, Italian National Research Council (C.N.R.), Via Salaria km 29, 300-00015 Monterotondo (Rome), Italy.
authors.forename: Donatella
authors.initials: D
authors.lastname: Capitani
authors.affiliation: Institute of Chemical Methodologies, Italian National Research Council (C.N.R.), Via Salaria km 29, 300-00015 Monterotondo (Rome), Italy. Electronic address: salvatore.fanali@cnr.it.
authors.forename: Salvatore
authors.initials: S
authors.lastname: Fanali
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000295:instrumentation / Q000379:methods; D017640:Silicates / Q000737:chemistry*; D013237:Stereoisomerism; D014640:Vancomycin / Q000737:chemistry*
chemical_list: D017640:Silicates; C487012:silica hydride; D014640:Vancomycin
keywords: Enantiomers; Herbicides; Nano-liquid chromatography; Non-steroidal anti-inflammatory drugs; Sub-2μm silica hydride particles; Vancomycin stationary phase