title: A comparison of the chromatographic properties of silica gel and silicon hydride modified silica gels.
abstract: The retention properties of a silica gel column and a type C silica (silicon hydride) column for bases, sugars and polar acids were compared in hydrophilic interaction chromatography (HILIC) mode with formic acid or ammonium acetate as aqueous phase modifiers. The type C silica column was much more retentive for a series of model bases than the silica gel column and, surprisingly, retention of bases increased on the type C silica column when, the higher pH, ammonium acetate containing mobile phase was used. The retention of sugars was greater on the type C silica column than on the silica gel column and also increased on the type C silica column with increased pH suggesting either a silanophilic mechanism of retention or some unknown mechanism. Three type C silica based columns, type C silica, cogent diamond hydride and a β-pinene modified column, which it was hoped might exert some additional stereochemical discrimination, were tested for metabolomic profiling of urine. In general the unmodified type C silica column gave the strongest retention of the many polar metabolites in urine and could provide a useful complement to established HILIC methods for metabolomic profiling.
authors.affiliation: Strathclyde Institute of Pharmacy and Biomedical Sciences, 161, Cathedral Street, Glasgow G4 0RE, UK.
authors.forename: Saud
authors.initials: S
authors.lastname: Bawazeer
authors.forename: Oliver B
authors.initials: OB
authors.lastname: Sutcliffe
authors.forename: Melvin R
authors.initials: MR
authors.lastname: Euerby
authors.forename: Sami
authors.initials: S
authors.lastname: Bawazeer
authors.forename: David G
authors.initials: DG
authors.lastname: Watson
mesh_terms: D002853:Chromatography, Liquid / Q000379:methods; D058428:Silica Gel / Q000737:chemistry*; D012825:Silicon / Q000737:chemistry*
chemical_list: D058428:Silica Gel; D012825:Silicon