Use of Leuco-Dyes in the Quantitative Colorimetric Microdetermination of Hemoglobin and Other Heme Compounds

[摘要] Sensitivity, stability, and specificity of the color-producing reaction of hydrogen peroxide with benzidine, leucomalachite green, or o -dianisidine were tested in numerous systems containing hemoglobin and other hemoproteins. Use of urea or low temperature (to -12 °C), or both, was highly beneficial, especially with leuco-malachite green, for which the color reaction was stable, after about 15 min, for longer than 24 h, with a colorless blank. Absorbance was 0.3 at a final hemoglobin concentration of 0.27 mg/liter. Nonspecific color produced by substances such as FeCl3 and ascorbic acid was completely eliminated. Of the three leuco-dyes studied, only benzidine yielded a completely linear calibration curve, but its relative instability and reported carcinogenicity are serious disadvantages. No system tested eliminated completely the known inhibition by plasma of the peroxidase activity of these leuco dyes.

[学科分类] 过敏症与临床免疫学