title: A simple method for measuring excess adsorption isotherms of organic eluent components on reversed-phase packing materials.
abstract: A simple frontal analysis method has been developed for the reliable measurement of excess adsorption isotherms of an organic component on reversed-phase adsorbents in a series of programmed concentration steps. In the present method, a peak, which is produced by refractive index change in column eluate, is detected at 589 nm; it represents the elution volume of the boundary. The method is applied to the measurement of the excess adsorption isotherms of organic eluent components from water on commercially available reversed-phase stationary phases. The results are in good agreement with the previously reported isotherms. We also measure the excess adsorption isotherms of organic eluent components from solutions containing electrolytes. There are not any interference peaks on the elution traces. The method is thus reliably applicable to the evaluation of the excess adsorption of organic eluent components in practical systems.
authors.affiliation: Department of Chemistry, Tokyo Institute of Technology, Tokyo, Japan.|Analytical and Quality Evaluation Research Laboratories, Daiichi Sankyo Co., Ltd., Hiratsuka, Japan.
authors.forename: Junji
authors.initials: J
authors.lastname: Ohashi
authors.affiliation: Department of Chemistry, Tokyo Institute of Technology, Tokyo, Japan.
authors.forename: Makoto
authors.initials: M
authors.lastname: Harada
authors.affiliation: Department of Chemistry, Tokyo Institute of Technology, Tokyo, Japan.
authors.forename: Tetsuo
authors.initials: T
authors.lastname: Okada
keywords: excess adsorption isotherms; frontal analysis; refractive index; reversed-phase liquid chromatography; staircase mode