Magnesium assay with calmagite or eriochrome black T reagents
AssigneeAmerican Monitor Corporation
InventorsJerry W. Denney, Robert L. Long
Life of this patent
Estimating the term…
Abstract
A colorimetric assay method and stabilized working reagents for the determination of magnesium in which an alkaline reagent containing a dye to complex magnesium reacts directly with the sample, requiring no protein-removal steps and no addition of substances to artificially correct for absorption differences of the metallized and free dye due to the presence of protein. The dye is either Calmagite or Eriochrome Black T. The reagent is buffered so that the pH is greater than about 9.0; the relative Van Slyke buffer value .beta.' of the reagent is greater than 1.
Claims38
A reagent for the determination of magnesium, comprising Calmagite and a strong buffer such that the pH of said reagent is greater than about 9.0 and the relative Van Slyke buffer value .beta.' of said reagent is greater than 1.
A reagent for the determination of magnesium, comprising Calmagite and a strong buffer such that the pH of said reagent is greater than about 9.0 and the relative Van Slyke buffer value .beta.' of said reagent is between 2 and 20.
A reagent for the determination of magnesium, comprising Calmagite and a strong buffer such that the pH of said reagent is greater than about 9.0 and the relative Van Slyke buffer value .beta.' of said reagent is between 3 and 15.
A reagent for the determination of magnesium, comprising Eriochrome Black T and a strong buffer such that the pH of said reagent is greater than about 9.0 and the relative Van Slyke buffer value .beta.' of said reagent is greater than 1.
A reagent for the determination of magnesium, comprising Eriochrome Black T and a strong buffer such that the pH of said reagent is greater than about 9.0 and the relative Van Slyke buffer value .beta.' of said reagent is between 2 and 20.
A reagent for the determination of magnesium, comprising Eriochrome Black T and a strong buffer such that the pH of said reagent is greater than about 9.0 and the relative Van Slyke buffer valve .beta.' of said reagent is between 3 and 15.
A reagent kit for the colorimetric determination of magnesium, said kit comprising:
- (a) a first reagent comprising a dye for binding magnesium, said dye selected from the group consisting of Calmagite and Eriochrome Black T;
- and
- (b) a second reagent comprising a strong buffer such that, when said second reagent is combined with said first reagent, the resulting reagent mixture has a pH of greater than about 9.0 and a relative Van Slyke buffer value .beta.' greater than 1.
A reagent kit for the colorimetric determination of magnesium, said kit comprising:
- a) a first reagent comprising a dye for binding magnesium, said dye selected from the group consisting of Calmagite and Eriochrome Black T;
- and
- (b) a second reagent comprising a strong buffer such that, when said second reagent is combined with said first reagent, the resulting reagent mixture has a pH of greater than about 9.0 and a relative Van Slyke buffer value .beta.' between 2 and 20.
A reagent kit for the colorimetric determination of magnesium, said kit comprising:
- (a) a first reagent comprising a dye for binding magnesium, said dye selected from the group consisting of Calmagite and Eriochrome Black T;
- and
- (b) a second reagent comprising a strong buffer such that, when said second reagent is combined with said first reagent, the resulting mixture has a pH of greater than about 9.0 and a relative Van Slyke buffer value .beta.' between 3 and 15.
A stabilized reagent for the determination of magnesium, comprising:
- (a) a dye selected from the group consisting of Calmagite and Eriochrome Black T;
- (b) a buffer selected from the group consisting of monoethanolamine, diethanolamine, triethanolamine, diethylamine, 2-amino-2-methyl-1-propanol and 3-(cyclohexylamino)-propanesulfonic acid, such buffer being sufficient that the relative Van Slyke buffer value .beta.' of said reagent is between about 3 and 15;
- and
- (c) a stabilizing agent selected from the group consisting of dimethylsulfoxide, a non-ionic surfactant, and a mixture of dimethylsulfoxide and a non-ionic surfactant.
Dependencies are inferred from the claim text.