title: High efficiency, narrow particle size distribution, sub-2 μm based macrocyclic glycopeptide chiral stationary phases in HPLC and SFC.
abstract: State of the art chiral chromatography still employs 3-5 μm bonded or immobilized chiral selectors in 10-25 cm columns. With the availability of 1.9 μm narrow particle size distribution (NPSD) silica, it is now possible to make ever shorter, high efficiency columns practical for sub-minute chiral separations. Three macrocyclic glycopeptides (teicoplanin, teicoplanin aglycone, and vancomycin) were bonded onto 1.9 μm NPSD particles. Such packed columns had ∼80% lower backpressure as compared to polydisperse (PD) 1.7 μm silica materials when using the same mobile phase. The decreased backpressure allowed for diminution of frictional heating and allowed for the use of the 1.9 μm NPSD particle based columns at high flow rates. The 1.9 μm NPSD particle based columns showed up to 190,000 plates m(-1) for chiral molecules and 210,000 plates m(-1) for achiral probes. Representative enantiomeric separations are shown for wide classes of compounds, including different types of amino acids, β-blockers, and pharmaceutically important heterocyclic compounds such as oxazolidinones. Applications in three liquid chromatography modes, namely, reversed phase, polar organic mode and normal phase chiral separations were shown with resolution values ranging from 1.5 to 5.7. Additionally, the same columns were used with supercritical fluid chromatography (SFC) for ultrafast separations.
authors.affiliation: Department of Chemistry and Biochemistry, University of Texas at Arlington, 700 Planetarium Place, Arlington, TX 76019-0065, USA.
authors.forename: Chandan L
authors.initials: CL
authors.lastname: Barhate
authors.affiliation: Department of Chemistry and Biochemistry, University of Texas at Arlington, 700 Planetarium Place, Arlington, TX 76019-0065, USA.
authors.forename: M Farooq
authors.initials: MF
authors.lastname: Wahab
authors.affiliation: Department of Chemistry and Biochemistry, University of Texas at Arlington, 700 Planetarium Place, Arlington, TX 76019-0065, USA.
authors.forename: Zachary S
authors.initials: ZS
authors.lastname: Breitbach
authors.affiliation: Sigma-Aldrich/Supelco, 595 North Harrison Road, Bellefonte, PA 16823, USA.
authors.forename: David S
authors.initials: DS
authors.lastname: Bell
authors.affiliation: Department of Chemistry and Biochemistry, University of Texas at Arlington, 700 Planetarium Place, Arlington, TX 76019-0065, USA. Electronic address: sec4dwa@uta.edu.
authors.forename: Daniel W
authors.initials: DW
authors.lastname: Armstrong
keywords: Chiral separation; High efficiency ultrafast separation; Narrow particle size distribution; Sub-2 μm; Supercritical fluid chromatography; Ultrahigh pressure liquid chromatography