PROCEEDINGS |
The presence of contaminants in dyes used for biological staining can cause variations in their staining properties. This problem has been documented as the cause of anomalous histochemical staining results. A prerequisite for the standardization of biological stains is the availability of pure dyes that do not vary in composition from batch to batch. pH-Zone-refining countercurrent chromatography (CCC) has been recently developed as a preparative-scale method for the purification of multigram quantities of closely-related dyes (including positional isomers). In this presentation, it is proposed that pH-zone-refining CCC would facilitate the attainment (qualitatively and quantitatively) of the pure dyes necessary for the standardization of biological stains.