title: Superheated water as eluent in high-temperature high-performance liquid chromatographic separations of steroids on a polymer-coated zirconia column.
abstract: High-temperature liquid chromatography (HTLC), with a superheated water mobile phase, has been shown to be a feasible replacement for medium-polarity acetonitrile-water mixtures as an eluent in reversed-phase HPLC. Instrumental parameters of flow-rate, injection volume and mobile phase preheating were shown to have significant effects on the quality of the chromatographic peaks. The selectivity and retention patterns of testosterone and several related compounds were investigated on a porous zirconia, polybutadiene-coated column at temperatures up to 200 degrees C and compared with that of a porous silica, octadecylsilane-coated column and the zirconia column under traditional reversed-phase conditions of an acetonitrile-water mobile phase at 40 degrees C. The selectivity differences observed for testosterone and related compounds show that the separation mechanisms are complementary and unique selectivity is obtained with the zirconia column under HTLC conditions.
authors.affiliation: Analytical Sciences, ALZA Corporation, Mountain View, CA 94043-7210, USA. steve.fields@alza.com
authors.forename: S M
authors.initials: SM
authors.lastname: Fields
authors.forename: C Q
authors.initials: CQ
authors.lastname: Ye
authors.forename: D D
authors.initials: DD
authors.lastname: Zhang
authors.forename: B R
authors.initials: BR
authors.lastname: Branch
authors.forename: X J
authors.initials: XJ
authors.lastname: Zhang
authors.forename: N
authors.initials: N
authors.lastname: Okafo
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D006358:Hot Temperature; D015394:Molecular Structure; D011108:Polymers; D012680:Sensitivity and Specificity; D013739:Testosterone / Q000737:chemistry / Q000302:isolation & purification*; D014867:Water; D015040:Zirconium
chemical_list: D011108:Polymers; D014867:Water; D013739:Testosterone; D015040:Zirconium; C028541:zirconium oxide