STABILIZED TWO-PART HEMATOXYLIN SOLUTION UTILIZING pH ADJUSTMENT

6, wherein the stabilized hematoxylin formulation comprises a hematoxylin dye and an acid in an amount ranging from about 0.2% to about 4% by total volume of the stabilized hematoxylin solution;

• and (b) contacting the biological sample with the hematoxylin staining solution having the pH ranging from about 2.4 to about 2.6.

A method of staining a biological sample, comprising mixing a first component and a second component to form a hematoxylin staining solution, and contacting the biological sample with the formed hematoxylin staining solution, wherein the first component comprises a stabilized hematoxylin formulation comprising a hematoxylin dye and an acid in an amount ranging from about 0.1% to about 10% by total volume of the stabilized hematoxylin formulation, and wherein the stabilized hematoxylin formulation has a pH of less than 2.4;

• and wherein second component comprises a strong base or a buffer, the second component provided in an amount relative to the first component such that when the first and second components are mixed, the pH of the hematoxylin solution increases to between about 2.4 to about 2.6.

A kit comprising a first component and a second component,

• the first component comprising a stabilized hematoxylin formulation comprising a hematoxylin dye and an acid in an amount ranging from about 0.1% to about 10% by total volume of the stabilized hematoxylin formulation, and wherein the stabilized hematoxylin formulation has a pH of less than 2.4;
• and
• the second component comprising a strong base or a buffer, the second component provided in an amount relative to the first component such that when the first and second components are mixed, the pH of the hematoxylin solution increases to between about 2.4 to about 2.6.