The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 01, 1992
Filed:
Feb. 08, 1991
Bernd Glatz, Leonberg, DE;
Hewlett-Packard Company, Palo Alto, CA (US);
Abstract
Herein described is a process for the chromatographic determination of ions, particularly anions on a reversed-phase column, in which sample ions are introduced into a mobile phase containing a modifier and a counterion, the mobile phase with the modifier, counterion and sample ions is passed through the column and, after separation with the aid of a suitable detection method, preferably an indirect UV-detection method, the individual sample ions are determined quantitatively via the decrease the counterion concentration in the eluent. In this process the mobile phase is a mixture of water an an organic solvent and has a pH-value of more than 5. The modifier used is a quaternary ammonium hydroxide of formula ##STR1## in which at least one radical is a straight-chained or branched alkyl radical with at least 8 and up to 20, more particularly 12 to 18 C-atoms. Prior to the passage of the mobile phase containing the sample ions, the reversed-phase column is preferably brought into equilibrium with the modifier, particularly with the modifier and the counterior. Trimethyl hexadecyl ammonium hydroxide is preferable used as the quaternary ammonium hydroxide. Also described herein is the use of said quaternary ammonium hydroxides for the quantitative chromatographic determination of ions and in particular for the determination of inorganic anions, as well as a reversed-phase material chromatographic column obtained through the conditioning with the modifier.