Analysis of regulatory dye in diesel petroleum

This study is concerned with alternative analytical methods for determining the content of red dye in diesel fuel. It was found that a preconcentration step consisting of adsorption chromatography on silica gel, followed by either HPLC or gas chromatography¯mass spectrometry greatly increases the sensitivity of the method employed. Structures for the main components in the commercial dye are proposed based on NMR data.