A Comparison of Assay Values with Actual Staining Obtained from Commercial Hemateins

Abstract

A progressive dilution method was developed for a measure of staining activity. This made possible a comparison of staining activity of the hematein-aluminum complexes of 9 batches of commercial hemateins and their actual hematein content. It was found that the lower the actual hematein content the poorer was the correlation with staining activity. Also in the samples with lower hematein content the blue color of the hematein-aluminum complex was more or less replaced by brown color. Apparently contaminating material in these commercial hemateins with low hematein content compete with the hematein-aluminum complex for staining sites. Unless extremely pure hematein can be supplied the use of hematein as a stain cannot be recommended.