Various dyes are widely used in food, textile and pharmaceutical industries. Dies are aromatic compounds containing ionizable groups. Methylene blue, crystal violet lactone and crystal violet were separated on a Primesep D HPLC column. Method can be used for separation of other dyes and pigments that are basic and hydrophobic in nature.
Analysis of Methylene Blue Purity in Reversed-Phase Cation-Exchange and Reversed-Phase Cation-Exclusion Modes
Methylene blue is a heterocyclic dye with a wide range of use in biology and chemistry. Purity of dyes rarely exceed 70% and separation of methylene blue and related impurities is required. Two alternative methods for purity analysis were developed on Primesep C and Primesep D mixed-mode HPLC columns. Primesep C is a reversed-phase cation-exchange (anion-exclusion column) column and Primesep D is reversed-phase anion-exchange (cation-exclusion) column. Various buffers can be used for the method. Depending on the buffer, method can be compatible with UV, LC/MS and prep chromatography. Method can be used for prep separation of methylene blue and related impurities.