GLUCOSE DETERMINATION METHOD EMPLOYING ORTHOTOLUIDINE

• US 3,615,228 A
• Filed: 11/20/1969
• Issued: 10/26/1971
• Est. Priority Date: 11/20/1969
• Status: Expired due to Term

• Current Assignee: Bernard J. Thiegs, John D.I. Giorgio, Robert F. Mack
• Original Assignee: Bernard J. Thiegs, John D.I. Giorgio, Robert F. Mack
• Inventors: Thiegs, Bernard J., Mack, Robert F., Giorgio, John Di
• Primary Examiner(s): Wolk, Morris O.
• Assistant Examiner(s): Katz, Elliot A.
• Application Number:
  US04/878,573
• Time in Patent Office: 705 Days
• Field of Search: 23/230,23B,253TP 252/408 195/103.5
• US Class Current: 436/95
• CPC Class Codes: G01N 33/66 involving blood sugars, e.g. galactose
• CPC Class Codes: Y10T 436/144444 Glucose

Abstract

An improved orthotoluidine reagent composition for use in determination of glucose in biological fluids effective sufficient hydrazine to provide a uniform intensity of color when the composition is reacted with a predetermined amount of glucose, such as a standard solution.

Claims

2. The method of claim 1 wherein the hydrazine is added in an amount sufficient to provide a hydrazine concentration of from about 60 to about 200 micromoles of hydrazine per 100 milliliters of reagent composition.

3. The method of claim 1 wherein the hydrazine is added in the form of hydrazine hydrate.

4. The method of claim 1 wherein the reagent composition is prepared by mixing together orthotoluidine, thiourea and glacial acetic acid in predetermined amounts, and wherein the hydrazine is mixed with the orthotoluidine prior to preparation of the reagent composition.

5. The method of claim 4 wherein the hydrazine is employed in an amount sufficient to provide from about 9 to about 20 micromoles of hydrazine per gram of orthotoluidine.

6. In a reagent composition useful for determination of glucose by measuring the intensity of color produced by the reaction of glucose with orthotoluidine comprising a solution of orthotoluidine in glacial acetic acid, the concentration of orthotoluidine being from about 5 to about 10 grams of orthotoluidine per 100 milliliters of said solution;

the improvement wherein the reagent composition further comprises from about 9 to about 20 micromoles of hydrazine per gram of orthotoluidine, said hydrazine being sufficient to decrease the intensity of the color produced when said composition is reacted with glucose.

7. The composition of claim 6 further comprising from about 0.1 to about 1 gram of thiourea.

8. The composition of claim 6 wherein the composition consists essentially of about 9 grams of orthotoluidine and about 0.5 gram of thiourea per 100 milliliters of composition and contains from about 80 to about 180 micromoles of hydrazine per 100 milliliters.

9. The composition of claim 8 further comprising from about 1.8 to about 2.1 milligrams of glucose per 100 milliliters, and wherein said hydrazine is present in an amount sufficient to decrease the intensity of color obtained by reaction of said glucose with said orthotoluidine to provide an intensity of said color equivalent to an absorbance of from about 0.30 to about 0.34 for light having a wavelength of from 590 to 620 millimicrons.