Glucuronic acid color tests

Determination.—Analytical methods for determination of D-glucuronic acid have been discussed recently by Artz and Osman.6 Decarboxylation is the most accurate method, and is generally used for determination of D-glucuronic acid from plant sources. Some modifications have been introduced recently for small quantities.26 Other methods, such as reduction, measurement of optical rotation, and an array of color tests,27 are of limited value. Levvy28 has applied a cerimetric method using a Conway burette. 

When the Legal test (alkaline nitroprasside), ordinarily used for the detection of acetone, is applied to urine containing glucuronic acid conjugation products, a red to violet color is developed which is destroyed or changed to orange by addition of acetic acid (259). The red color developed by acetone under the same conditions is not destroyed by acidifying with acetic acid. 

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