Separation of vitamins by supercritical fluid chromatography with water-modified carbon dioxide as the mobile phase

Supercritical fluid chromatography (SFC) has become a technique for solving problems that are difficult to be monitored by other chromatographic methods. However, the most widely used fluid, is no more polar than hexane. Polar samples which are difficult to be analyzed with pure supercritical CO(2) because of their high polarity can be separated by adding polar modifiers to supercritical CO(2). In this paper various vitamins were well separated using water-modified supercritical CO(2) fluid. The amount of water dissolved in supercritical CO(2) was measured using an amperometric microsensor made of a thin film of perfluorosulfonate ionomer (PFSI).