Glycyrrhizin assay

Assay Not less than 22.0% and not more than 32.0% of monoammonium glycyrrhizinate (C42H65N016), calculated on the dried basis. 

Procedure Separately inject, in duplicate, 10- xL volumes of the Standard Solution and the Assay Solution into the chromatograph, and determine the mean peak area for each solution. Calculate the percent monoammonium glycyrrhizinate, equivalent to C HgjNOjg, in the portion of sample taken by the formula... 

Shan, S. J., Tanaka, H., and Shoyama, Y. 2001. Enzyme-linked immunosorbent assay for glycyrrhizin using anti-glycyrrhizin monoclonal antibody and an eastern blotting technique for glucuronides of glyc-yrrhetic acid. Anal Chem, 73 5784-90. 

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