title: Diol-bonded silica gel as a restricted access packing forming a binary-layered phase for direct injection of serum for the determination of drugs.
abstract: Direct serum injection for drug determinations can be achieved on a diol-bonded silica gel as a restricted access packing. The diol-bonded phase, 3-(2,3-dihydroxypropoxy)propylsilylsilica, contains two different functions, a hydrophilic function at the tip of the single chemical bond and a hydrophobic function on the inside part of the bond to form a "binary-layered phase" on the support surface. Proteins, as large molecules, contact only the hydrophilic surface of the diol phase, and they are eluted at the solvent front based on size-exclusion chromatography. On the other hand, small molecules such as synthetic drugs are retained on the internal hydrophobic function and separate based on reversed-phase chromatography. Accordingly, the diol-bonded silica gel performs as a restricted access packing for direct serum injection for the determination of relatively hydrophobic drugs.
authors.affiliation: School of Pharmaceutical Sciences, Kitasato University, Tokyo, Japan.
authors.forename: N
authors.initials: N
authors.lastname: Nimura
authors.forename: H
authors.initials: H
authors.lastname: Itoh
authors.forename: T
authors.initials: T
authors.lastname: Kinoshita
mesh_terms: D001774:Blood Chemical Analysis; D002851:Chromatography, High Pressure Liquid / Q000295:instrumentation*; D006801:Humans; D004364:Pharmaceutical Preparations / Q000032:analysis*; D058428:Silica Gel; D012822:Silicon Dioxide; D013056:Spectrophotometry, Ultraviolet
chemical_list: D004364:Pharmaceutical Preparations; D058428:Silica Gel; D012822:Silicon Dioxide