Separation of aromatic amines by an open‐tubular capillary electrochromatography method

A new and simple open‐tubular CEC (OT‐CEC) method with a novel diblock copolymer poly(butyl methacrylate)₇₁‐block‐poly(glycidyl methacrylate)₉ as the coating based on its self‐assembled properties has been developed. Compared with the bare capillary, this coating could act as a surfactant and improve the separation efficiency of aromatic amines. Meanwhile, the effects of pH value, buffer concentration, and the copolymer block ratio on the separation efficiencies were investigated in detail. It has been found that the three tested aromatic amines could be baseline separated by the OT‐CEC method with the cooperation of SDS. The proposed OT‐CEC method showed good repeatability with RSDs <3.2% for testing the EOF. Moreover, it was also well validated by satisfactory linearity and favorable recovery, which ensured its successful application in the separation of aromatic amines in nail polish samples. The results revealed the potential applicability of the OT‐CEC method in cosmetic analysis.